- Spectral, thermal, and X-ray studies on some new bis and tris-hydrazine and hydrazinium metal pyruvates
-
Some bis-hydrazine metal pyruvates of transition metal ions of the formula M[CH3COCOO]2 [N2H4]2, where M = Co, Ni, Zn or Cd, tris-hydrazine metal pyruvates of the formula M[CH3COCOO]2
- Raju,Sivasankar
-
-
Read Online
- Electric field formation during combustion of single metal particles
-
A strong electric field formed during the initial stage of the combustion of single Zr, Ti, Fe, and Ni particles. The electric field lasted for 20-400 ms and decayed before the particle temperature reached its maximum. A low voltage was generated during the combustion of particles initially surrounded by a thick oxide film or when the ambient oxygen concentration was low. A decrease in the rate of oxygen transport to the reaction zone generated a bipolar signal during the combustion of Zr and Ti and/or electric oscillations of 0.5-10 Hz. Melting of either the reactants, or intermediate or final products annihilated the electrical field. The maximum voltage and current were attained for particles of ~0.8 mm diam. The largest unipolar electric voltage and current were produced during the combustion of either a Zr or a Ti particle (~2 V and ~100 mA). A rapid increase in the rate of temperature rise in Zr and Ti particles followed the annihilation of the electric field. It may have been caused by Joule heating following electric breakdown through the oxide film. A shift from homogeneous to relay-race combustion occurred upon increasing the distance between particles in a row. This shift affected the qualitative features of the generated electric field as well as the temperature at which it formed.
- Martirosyan,Filimonov,Nersesyan,Luss, Dan
-
-
Read Online
- K4Ni3O6 and KNa2Ni 2O4, new quasi one-dimensional oxonickelates(II, III)
-
Two new quasi one-dimensional alkali metal oxonickelates, K 4Ni3O6 and KNa2Ni2O 4, were obtained by the azide/nitrate route starting from respective stoichiometric mixtures of KN3, KNO3, NaN3, NaNO3, and NiO. According to the X-ray analyses of the crystal structures [K4Ni3O6: C2/m, Z = 2, a = 899, 53(3), b = 610, 24(2), c = 778.75(2) pm, β = 91.665(2)°, R1 = 0.030, wR2 = 0.088; KNa2Ni2O4: P21/n, Z = 4, a = 573.70(2), b = 1072.89(3), c = 844.93(2) pm, β = 102.916(2)°, R1 = 0.038, wR2 = 0.108], the main feature common to both crystal structures are undulating 1 ∞NiO2 chains consisting of planar, edge-sharing NiO4 squares. The magnetic susceptibilities for both compounds indicate onset of antiferromagnetic ordering at about 5 K. Evaluations of the Curie-Weiss fits result in calculated magnetic moments higher than expected for the respective spin only values, implying some orbital contribution. Below the Neel temperature spin flop or meta-magnetism is observed for both compounds.
- D Strok Signuris, Katarina,Nuss, Juergen,Jansen, Martin
-
-
Read Online
- Preparation and characterization of NiO nanoparticles from thermal decomposition of the [Ni(en)3](NO3)2 complex: A facile and low-temperature route
-
NiO nanoparticles with an average size of 15 nm were easily prepared via the thermal decomposition of the tris(ethylenediamine)Ni(II) nitrate complex [Ni(en)3](NO3)2 as a new precursor at low temperature, and the nanoparticles were characterized by thermal analysis (TGA/DTA), X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), UV-Vis spectroscopy, BET specific surface area measurement, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and magnetic measurements. The magnetic measurements confirm that the product shows a ferromagnetic behavior at room temperature, which may be ascribed to a size confinement effect. The NiO nanoparticles prepared by this method could be an appropriate photocatalytic material due to a strong absorption band at 325 nm. This method is simple, fast, safe, low-cost and also suitable for industrial production of high purity NiO nanoparticles for applied purposes.
- Farhadi, Saeid,Roostaei-Zaniyani, Zeinab
-
-
Read Online
- Spin-gap formation and thermal structural studies in reduced hybrid layered vanadates
-
Reduced layered M(C4H4N2)V 4O10 ((I, M = Co; II, M = Ni; III, M = Zn); C 4H4N2 = pyrazine, pyz) hybrid solids were synthesized via hydrothermal reactions at 200-230°C, and their structures determined by single-crystal X-ray diffraction (Cmcm, No. 63, Z = 4; a = 14.311(2), 14.2372(4), 14.425(1) A; b = 6.997(1), 6.9008(2), 6.9702(6) A; and c = 11.4990(8), 11.5102(3), 11.479(1) A; for I, II, and III, respectively). All three solids are isostructural and contain V 4O102- layers condensed from edge- and corner-shared VO5 square pyramids. A single symmetry-unique V atom is reduced by 1/2 electron (on average) and bonds via its apical oxygen atom to interlayer M(pyz)2+ chains. Magnetic susceptibility measurements show a strong temperature dependence and a Curie constant that is consistent with two randomly localized spins per V4O102- formula for III. Further, the unusual discovery of a remarkably well-defined transition to a singlet ground state, as well as formation of a spin gap, is found for III at 22(1) K. The temperature-dependent electrical conductivities show apparent activation energies of 0.36 (I), 0.46 (II), and 0.59 eV (III). During heating cycles in flowing N2, the samples exhibit weight losses corresponding to the removal of predominantly pyrazine, pyrazine fragments, and CO2 via reaction of pyrazine with the vanadate layer. The complete removal of pyrazine without loss of crystallinity is found for well-ground samples of I and III. The SEM images of I and II after heating at 400-500°C show relatively intact crystals, but at 600°C further structural collapse results in the formation of macropores at the surfaces.
- Yan, Bangbo,Luo, Junhua,Dube, Paul,Sefat, Athena S.,Greedan, John E.,Maggard, Paul A.
-
-
Read Online
- The combined effect of mechanical and thermal energy on the solid-state formation of NiFe2O4 from the system 2NiCO3·3Ni(OH)2·4H2O-FeC2O4·2H2O
-
Spinel-type ferrites MFe2O4 (M = Ni, Zn, Mn, Co, Mg) are among the most important magnetic materials and they are prepared mostly by solid-state reaction at elevated temperatures. We proposed in the past [V. Sepelak, I. Bergmann, A. Feldhoff, P. Heitjans, F. Krumeich, D. Mmenzel, F.J. Litterst, S.J. Campbell, K. Becker, J. Phys. Chem. C 111 (2007) 502612; S. Bid, P. Sahu, S.K. Pradhan, Physica E 39 (2007) 175] a mixed synthetic route that uses both mechanical and thermal energy. In the present work the strategy is applied to the preparation of NiFe2O4 starting from mixtures of 2NiCO3·3Ni(OH)2·4H2O-FeC2O4·2H2O subjected to both mechanical and thermal annealing. TG/DSC measurements allowed to obtain information on the reaction mechanism and also a ΔH for the reaction between the constituent oxides yielding NiFe2O4 in good agreement with the deduced from the data of ΔG° versus T. The XRPD of the samples recovered after the TG/DSC runs shows the reflexions of NiFe2O4 only when starting from milled mixture. NiFe2O4 can be prepared by thermal treatment of physical mixtures 2NiCO3·3Ni(OH)2·4H2O-10FeC2O4·2H2O by 36 h at 1100 °C. On the contrary 12 h at 400 °C yield XRPD-phase pure NiFe2O4. Samples of NiFe2O4 obtained from the milled mixture show a surface area that decrease by increasing the synthesis temperature from 400 °C to 700 °C. On the basis of measurements of molar thermal capacity, it is demonstrated that NiFe2O4 can be obtained by a 12 h annealing at 450 °C of the mechanically activated mixture.
- Berbenni, Vittorio,Milanese, Chiara,Bruni, Giovanna,Marini, Amedeo
-
-
Read Online
- Catalytic hydrocarboxylation of acetylene to acrylic acid using Ni2O3 and cupric bromide as combined catalysts
-
A non-petroleum route to produce acrylic acid was investigated through hydrocarboxylation of acetylenewith CO and water in the presence of Ni2O3and cupric bromide as combined catalysts. The activity of Ni2O3was compared with various homogeneous catalysts; the effect of initial total pressure, reactiontemperature, molar ratio of CO/C2H2, the volume ratio of solvent/water, the catalyst amount and the roleof promoters have been studied in detail. It was found that the acrylic acid space-time-yield as high as764.6 mol AA/(mol Ni h) was obtained under the optimal experimental conditions. The Ni2O3catalyst could be reused at least five times without obvious loss of activity. The characterization of recoveredcatalysts by XRD, XPS, SEM and TG-DTG revealed that the state of nickel remains unchanged during thereaction, and there are three types of soft coke deposited on the surface of the catalyst. The catalysts canbe regenerated through calcination within 400°C according to TG curve.
- Lin, Tie Jun,Meng, Xuan,Shi, Li
-
-
Read Online
- Synthesis, characterization, corrosion inhibition of mild steel in HCl (0.5?N) solution and solid-state electrical conductivity of new Co(II), Ni(II), Cu(II) and Zn(II) complexes
-
This work consists of a study of the corrosion-inhibiting and semiconducting properties of new binuclear Co(II), Ni(II), Cu(II) and Zn(II) complexes with a Schiff base, H2L, obtained from the 2:1 M condensation of salicylaldehyde and o-dianisidine, respectively. Elemental, spectral and thermal analyses were used to characterize these complexes. The magnetic susceptibilities of these complexes were also determined. Weight loss, potentiodynamic polarization and scanning optical microscopy were the techniques used to investigate the efficiency of these new compounds as corrosion inhibitors. The antibacterial activity of the compounds was measured against sulfate-reducing bacteria. It was found that inhibition occurs via the chemisorption of metal complexes on the steel surface. This absorption obeys the Langmuir adsorption isotherm model.
- Nassar,Hassan,Elkmash
-
-
Read Online
- Investigation of porous ni-based metal-organic frameworks containing paddle-wheel type inorganic building units via high-throughput methods
-
In the search of Ni based metal-organic frameworks (MOFs) containing paddle-wheel type building units, three chemical systems Ni2+/HnL/ base/solvent with HnL = H3BTC (1,3,5-benzenetricarboxylic acid), H3BTB (4,40,400,-benzene-1,3,5-triyl-tris- (benzoic acid)), and H2BDC (terephthalic acid) were investigated using high-throughput (HT) methods. In addition to the conventional heating, for the first time HT microwave assisted synthesis of MOFs was carried out. Six new compounds were discovered, and their fields of formation were established. In the first system, H3BTC was employed and a comprehensive HT-screening of compositional and process parameters was conducted. The synthesis condition for the Ni paddle-wheel unit was determined and two compounds [Ni3(BTC)2(Me 2NH)3]·(DMF)4(H2O) 4 (1a) and [Ni6(BTC)2(DMF)6(HCOO) 6] (1b) were discovered (Me2NH = dimethylamine, DMF = dimethylformamide). In the second system, the use of the extended tritopic linker H3BTB and the synthesis conditions for the paddle-wheel units led to the porous MOF, [Ni3(BTB)2(2-MeIm) 1.5(H2O)1.5]·(DMF)9- (H 2O)6.5 (2), (2-MeIm = 2-methylimidazole). This compound shows a selective adsorption of H2O and H2 with a strong hysteresis. In the third system, H2BDC was used, and the base (DABCO) was incorporated as a bridging ligand into all structures. Thus, two pillared layered porous MOFs [Ni2(BDC)2(DABCO)]·(DMF) 4(H2O)1.5(3a) and [Ni2(BDC) 2(DABCO)]·(DMF)4(H2O)4(3b) as well as a layered compound [Ni(BDC)(DABCO)]·(DMF)1.5(H 2O)2 (3c) were isolated. The 3a and 3b polymorphs of the [Ni2(BDC)2(DABCO)] framework can be selectively synthesized. The combination of microwave assisted heating, low overall concentration, stirring of the reaction mixtures, and an excess of DABCO yields a highly crystalline pure phase of 3b. The fields of formation of all compounds were established, and scale-up was successfully performed for 1b, 2, 3a, 3b, and 3c. All compounds were structurally characterized. In addition to IR, elemental and TG analyses, gas and vapor sorption experiments were carried out.
- Maniam, Palanikumar,Stock, Norbert
-
-
Read Online
- Cs2NiO2 revisited. Crystal structure and magnetic properties
-
Single crystals as well as microcrystalline powders of Cs 2NiO2 were obtained via the azide/nitrate route from appropriate mixtures of CsN3, CsNO3 and NiO. The single-crystal structure analysis confirmed that Cs2NiO2 crystallizes in the tetragonal space group I4/mmm (Z = 2, a = 4.4090(3), c = 13.576(3) A , R1 = 0.036, wR2 = 0.093). Above 45 K, Cs2NiO 2 is paramagnetic, and an analysis based on the Curie-Weiss law has resulted in μ = 2.89 μB paramagnetic units, θ = ?30.8 K and TN ~ 20 K.
- Duris, Katarina,Jansen, Martin
-
-
Read Online
- Thermolysis of Coprecipitated Copper(II)-Nickel(II) Hydroxides
-
Coprecipitated copper(II)-nickel(II) hydroxides and mechanical mixtures of these were obtained at varied metal ion ratio and time of mother liquor aging and studied by potentiometric titration, chemical and differential thermal analyses, IR spectroscopy,
- Kopylovich,Kirillov,Baev
-
-
Read Online
- Thermal and kinetic study of nickel trifluoromethanesulphonate, trifluoroacetate and acetate
-
The reason of comparing thermal behaviour and kinetics of some nickel compounds, is justified by the influence of anion on it, besides supplying information on the stability of the salts. In this work, Ni(TMS) 2?6H2O, Ni(TFA)2/
- De Souza,Sousa,Paiva,Borges,Melo,Scatena Jr.
-
-
Read Online
- Synthesis and thermal decomposition of Zn(tda)H2O [tda = S(CH2COO)22-]
-
A novel two-dimensional coordination polymer Zn(tda)H2O [tda = S(CH2COO)22-] was synthesized under hydrothermal conditions. The compound crystallized in monoclinic space group P21 with a = 16.4154(17) A, b = 5.2133(6) A, c = 16.4210(17) A, β = 114.165(2)°, V = 1282.1(2) A3, and Z = 8. The structure features two-dimensional, noncentrosymmetric networks with a pseudohexagonal network of Zn2+ coordinated by tda and water molecules. Zn(tda)H2O decomposed at T > 300°C to form a ZnO sponge with a surface area ~ 40 m 2/g, which makes it an attractive precursor for nanoporous ZnO.
- Wu, Ming-Cheng,Lee, Chi-Shen
-
-
Read Online
- Thermal degradation of acetate-intercalated hydroxy double and layered hydroxy salts
-
Two hydroxy double salts (HDSs), zinc copper hydroxy acetate (ZCA) and zinc nickel hydroxy acetate (ZNA), and an analogous layered compound, zinc hydroxy acetate (ZHA), have been prepared by a coprecipitation method. The thermal degradation of these materials was characterized via thermogravimetric analysis (TGA), differential thermal analysis (DTA), and TGA coupled with Fourier transform infrared spectroscopy of gas-phase products, TGA-FTIR. Loss of physisorbed and interlayer H2O was observed between 50 and 150°C for all compounds. Acetic acid, acetone, water, and CO2 were released at high temperatures with relative acetone yields found to be dependent on precursor identity, with very little formed from ZCA compared with ZHA and ZNA. Combined FTIR and XRD analysis of solid residues extracted at different points in the heating profile suggests that ketonization occurs via dissociative adsorption of acetic acid on ZnO surfaces. Nanometer-sized ZnO particles were formed from ZHA, showing slight preferential growth in the ZnO (002) lattice direction, while the presence of a second metal, Ni or Cu, served to retard ZnO crystallite growth at temperatures below 600°C and eliminate preferential growth. ZCA leads to the formation of reduced copper species (metallic copper and Cu2O) when heated to 250°C.
- Kandare, Everson,Hossenlopp, Jeanne M.
-
-
Read Online
- Facile Synthesis of Hollow Polyhedral (Cubic, Octahedral and Dodecahedral) NiO with Enhanced Lithium Storage Capabilities
-
A facile sacrificial-template method combined with a post annealing treatment was developed to synthesize uniform hollow polyhedral (cubic, octahedral and dodecahedral) NiO materials. The electrochemical and lithium-ion battery performances of the shape controlled hollow polyhedral NiO materials were examined, providing us with a description of the structure-performance correlations of hollow polyhedral anodes. The lithium-ion battery performance was found to be highly dependent on the hollow polyhedral NiO morphology. The hollow dodecahedral NiO (HD-NiO) electrode exhibited excellent cycling stability, high reversible capacity and good rate capacity compared to the other two NiO samples. At a current density of 0.1 A g-1, the hollow dodecahedral NiO electrode displayed an especially high capacity of 980 mAh g-1 after 100 cycles, which was much higher than that of the hollow cubic and octahedral NiO electrodes. Most important of all, when assembled with LiCoO2 to construct a full lithium-ion battery (HD-NiO//LiCoO2), the HD-NiO electrode exhibited a reversible capacity of 627 mAh g-1 at a current density of 0.1 A g-1 in the potential range of 1.0-3.8 V. These results clearly demonstrate that hollow polyhedral NiO has potential as an anode material in next generation lithium-ion battery systems with improved storage capacities.
- Lin, Feini,Wang, Hui,Wang, Gang
-
-
Read Online
- 49 Adsorption des Gaz par les Oxydes Pulverulents. I. Oxyde de Nickel
-
L'oxyde de nickel est obtenu par dissociation de l'hydroxyde de nickel pulvérulent. La cinétique de dissociation dépend de la forme de la nacelle contenant Ni(OH)2. Il est possible de montrer toutefois que cette déshydratation est une réaction topochimique d'ordre 2/3. Les propriétés adsorbantes de NiO obtenu vis-à-vis des gaz donneurs et accepteurs d'electrons sont sensiblement différentes de celles que présente l'oxyde obtenu par oxydation d'un film de nickel. On propose un mécanisme d'adsorption de CO et O2 expliquant l'empoisonnement du catalyseur par le gaz carbonique.
- Teichner,Marcellini,Rué, Et P.
-
-
Read Online
- Spectroscopic studies on Co(II), Ni(II), Cu(II) and Zn(II) complexes with a N4-macrocylic ligands
-
Complexes of cobalt(II), nickel(II), copper(II) and zinc(II) with a new tetraaza macrocyclic ligand have been synthesized and characterized by microanalyses, molar conductance, magnetic susceptibility, mass, thermogravimetric (TGA), IR, 1H and 13C NMR, electronic and ESR spectral studies. All the complexes are found to have the formula [MLX2]·nH2O and are six-coordinated with distorted octahedral geometry.
- Swamy,Pola, Someshwar
-
-
Read Online
- Simple and rapid synthesis of NiO/PPy thin films with improved electrochromic performance
-
Nickel oxide/polypyrrole (NiO/PPy) thin films were deposited by a two step process in which the NiO layer was electrodeposited potentiostatically from an aqueous solution of NiCl2·6H2O at pH 7.5 on fluorine doped tin oxide (FTO) coated conducting glass substrates, followed by the deposition of polypyrrole (PPy) thin films by chemical bath deposition (CBD) from pyrrole mixed with ammonium persulfate (APS). The NiO/PPy films were further characterized for their structural, optical, morphological and electrochromic properties. X-ray diffraction study indicates that the films composed of polycrystalline NiO and amorphous PPy. Infrared transmission spectrum reveals chemical bonding between NiO and PPy. Rectangular faceted grains were observed from scanning electron microscopy results. The electrochromic (EC) property of the film was studied using cyclic voltammogram (CV), chronoamperometry (CA) and optical modulation. The NiO/PPy presents superior EC properties than their individual counterparts. The coloration/bleaching kinetics (response time of few ms) and coloration efficiency (358 cm2/C) were found to be improved appreciably. The dramatic improvement in electrochemical stability (from about 500 c/b cycles for PPy to 10,000 c/b cycles for NiO/PPy) was observed. This work therefore demonstrates a cost-effective and simple way of depositing highly efficient, faster and stable NiO/PPy electrodes for EC devices.
- Sonavane,Inamdar,Dalavi,Deshmukh,Patil
-
-
Read Online
- Facile synthesis of nanocrystalline-assembled nest-like NiO hollow microspheres with superior lithium storage performance
-
Interconnected nest-like NiO hollow microspheres assembled from nanocrystallites are prepared by a facile hydrothermal method followed by annealing at 700 °C in air. It is noteworthy that the NiO hollow microspheres exhibit a very significant pseudocapacitive effect which makes a great contribution to the enhanced lithium storage performance. Benefiting from the advantages of unique nest-like nanoarchitecture and pseudocapacitive effect, the NiO hollow microspheres show high reversible capacity, superior cyclic performance, and excellent high rate capability. When used as anode materials for lithium ion batteries, the NiO hollow microspheres maintain a capacity of 650 mA h g-1 after 100 cycles at a current density of 1 A g-1. The capacity retention is 93%, which corresponds to a very small capacity decay of 0.07% per cycle. In particular, even at an ultra-high current density of 10 A g-1, the NiO electrode still delivers a stable discharge capacity of 457 mA h g-1.
- Li, Yanwei,Zheng, Yuanyuan,Yao, Jinhuan,Xiao, Jianrong,Yang, Jianwen,Xiao, Shunhua
-
-
Read Online
- Synthesis, structure analysis and thermodynamics of [Ni(H 2O)4(TO)2](NO3)2· 2H2O (TO = 1,2,4-triazole-5-one)
-
A novel complex [Ni(H2O)4(TO)2](NO3) 2· 2H2O (TO = 1,2,4-triazole-5-one) was synthesized and structurally characterized by X-ray crystal diffraction analysis. The decomposition reaction kinetic of the complex was studied using TG-DTG. A multiple heating rate method was utilized to determine the apparent activation energy (Ea) and pre-exponential constant (A) of the former two decomposition stages, and the values are 109.2 kJ mol-1, 10 13.80 s-1; 108 0 kJ mol-1, 1023.23 s-1, respectively The critical temperature of thermal explosion, the entropy of activation (ΔS≠), enthalpy of activation (ΔH≠) and the free energy of activation (ΔG ≠) of the initial two decomposition stages of the complex were also calculated. The standard enthalpy of formation of the new complex was determined as being-1464.55 ± 1.70 kJ mol-1 by a rotating-bomb calorimeter. Akademiai Kiado, Budapest, Hungary 2010.
- Chen, San-Ping,Li, Na,Wei, Qing,Gao, Sheng-Li
-
-
Read Online
- The activities of some metal oxides in promoting the thermal decomposition of potassium oxalate
-
Transition metal oxalates undergo anion breakdown in the solid state, many between 200 and 400°C, at much lower temperatures than the decomposition of potassium oxalate (at around 600°C) which melts at about 400°C. The present article reports studies of the chemical changes that occurred on heating equimolar crushed mixtures of potassium oxalate with each of a range of (mainly transition metal) oxides, ZnO, PbO, NiO, CuO, Cu2O, Fe2O3, Co3O4 and Cr2O3, in flowing air or hydrogen. The objective was to determine the abilities of these added oxides to promote oxalate ion breakdown. Possible mechanisms of catalysis appeared to include the intervention of the relatively less stable metal oxalates and/or a heterogeneous, catalytic reaction on the surfaces of the oxide or, under reducing conditions, on some of these metals. Melting might also be expected to increase reactivity. The results showed that the activities of these selected oxides in promoting oxalate anion breakdown were unexpectedly small. While these additives resulted in some reaction, there was evidence of the occurrence of some unpromoted decomposition of potassium oxalate during the final stages of heating (about 590-650°C) of all the mixtures studied. Under reducing conditions, in hydrogen, the limited catalytic activities of most oxides were further diminished, evidence that the metal formed was inactive. This contrasts with the autocatalytic reactions, envisaged as proceeding on the surfaces of metal product, in some solid state decompositions, such as nickel oxalate. Potassium oxalate melting was not associated with any increase in reactivity. It is concluded that these oxides do not interact appreciably with the ionic salt and potential oxalate intermediates do not form under these conditions. Surfaces of oxides and of metals similarly do not exhibit catalytic activity for the breakdown of ionic oxalate.
- Mohamed, Mohamed A,Galwey, Andrew K,Halawy, Samih A
-
-
Read Online
- Oxygen non-stoichiometry and reducibility of B-site substituted lanthanum manganites
-
LaMn0.8B'0.2O3+(δ) (B'=Ni, Zn, Cu) and LaMn0.5Cu0.5O3+(δ) perovskites were studied by temperature programmed reduction (TPR). Oxygen non-stoichiometry of the perovskite samples calcined in
- Patcas,Buciuman,Zsako
-
-
Read Online
- Some aspects of thermal decomposition of NiC2O4·2H2O
-
NiC2O4·2H2O decomposition in air and in helium was studied using TG, DTA and MS and FTIR analyses. It was found that the dehydration phase of reaction is not complete. Remaining water occluded in the pores of nickel oxalate is not liberated until the decomposition of oxalate ions starts. The residual water takes part in reaction of the basic nickel carbonate formation. The basic nickel carbonate decomposition is a source of traces of nickel oxide stated in the final product of decomposition along with metallic nickel. It was found that the double peak endothermic DTA signal which accompanies decomposition of nickel oxalate results from changing of the microscopic mechanism of reaction.
- Ma?ecka,Ma?ecki,Drozdz-Cie?la,Tortet,Llewellyn,Rouquerol
-
-
Read Online
- Synthesis, characterization, and catalytic performance of La1-xCexNi1-yZryO3 perovskite nanocatalysts in dry reforming of methane
-
La1-xCexNi1-yZryO3 perovskite nanocatalysts were prepared by a method called citrate sol-gel. The samples were studied by the methods as X-ray diffraction (XRD), temperature programmed reduction (TPR), and inductively coupled plasma (ICP) technique.The BET method was used to determine the specific surface area. In addition, scanning and transmission electron microscopy techniques were employed to study the morphology of the prepared samples31. The XRD patterns confirmed the formation of perovskite with well-crystallized structure in doping level up to x= 0.1 and y= 0.2. The results of morphology studies revealed that homogenous particles in nanometer range were achieved. Based on the TPR analysis, reduction process occurred at higher temperatures and became difficult as the doping level of Zr increases. The catalytic performance was studied in dry reforming of methane (DRM) with CO2. The catalyst La0.9Ce0.1Ni0.8Zr0.2O3 perovskite provides the highest catalytic performance. CH4 conversion was more than 60%, CO2 conversion was more than70% and the H2/CO molar ratio was ~1, respectively. Catalytic activity of La1-xCexNi1-yZryO3 nanocatalysts was enhanced when the doping level of Zr (y) increased up to 0.2, and the following result was obtained for H2/CO ratio: LaNiO3 > La0.9Ce0.1Ni0.8Zr0.2O3 > La0.9Ce0.1Ni0.9Zr0.1O3 > La0.9Ce0.1Ni O3
- Dezvareha, Parastoo,Aghabozorgb, Hamidreza,Hossaini Sadrc, Moayad,Zared, Karim
-
-
Read Online
- Syntheses, crystal structures, and properties of Five new transition metal molybdenum(VI) selenites and tellurites
-
Five new transition metal molybdenum(VI) selenites or tellurites, namely, TM(MoO3)(SeO3)(H2O) (TM = Mn, Co), Fe 2(Mo2O7)(SeO3)2(H2O), Cu2(MoO4)(S
- Zhang, Su-Yun,Jiang, Hai-Long,Sun, Chuan-Fu,Mao, Jiang-Gao
-
-
Read Online
- The synergistic influences of OH- concentration and electrolyte conductivity on the redox behavior of Ni (OH) 2 /NiOOH
-
The synergistic influences of the OH- concentration and electrolyte conductivity on the redox behavior of NiOOH/Ni (OH) 2 for nickel oxide-coated graphite electrodes are clearly demonstrated by voltammetric and impedance analyses. The increase in the OH-
- Hu, Chi-Chang,Chang, Kuo-Hsin,Hsu, Tung-Yu
-
-
Read Online
- Perovskites as Precursors for Ni/La2O3 Catalysts in the Dry Reforming of Methane: Synthesis by Constant pH Co-Precipitation, Reduction Mechanism and Effect of Ru-Doping
-
LaNiO3 perovskite is an interesting precursor for Ni/La2O3 catalysts for the dry reforming of methane at high temperatures. Precursors have been synthesized by co-precipitation without, with 2.5 at %, and with 5 at % Ru doping. The presence of Ru leads to a stabilization of the perovskite structure and hinders the decomposition into NiO and Ruddlesden-Popper mixed oxides Lan+1NinO3n+1, which was observed for the Ru-free sample upon calcination at 1000 °C (n = 3). Upon reduction in hydrogen, a mechanism involving at least two steps was observed and the first major step was identified as the partial reduction of the precursor leading to a LaNiO2.5-like intermediate. The second major step is the reduction to Ni metal supported on La2O3 independent of the Ru content of the catalyst. In the presence of Ru, indications for Ni-Ru alloy formation and for a higher dispersion of the metallic phase were found. The catalytic activity in DRM of the catalyst containing 2.5 % Ru was superior to the catalysts with more or without Ru. Furthermore, the propensity of coke formation was reduced by the presence of Ru.
- Kühl, Stefanie,Düdder, Hendrik,Girgsdies, Frank,K?hler, Kevin,Muhler, Martin,Behrens, Malte
-
-
Read Online
- Morphological and pharmacological investigation on some biopotent materials derived from substituted pyrimidine and imidazole enzyme constituents
-
Coordinating behavior of novel N2O type mixed ligand complexes (1-6) have been synthesized from substituted fluoropyrimidine [5-Fluorouracil (5-FU; A)] with biopotent imidazole enzyme constituents (B) viz., imidazole(him) and benzimidazole(bim) in the presence of Ni(II), Cu(II) and Zn(II) ions. Synthesized complexes were characterized by chemical analysis, spectral studies, magnetic moment and conductivity measurements. The results of chemical analysis and the observed low molar conductance values propose their stoichiometry to be 1:1:1 (M:A:B) with non-electrolytic nature. From the spectral data, it is inferred that the ligands A & B coordinate with M(II) ions in bi and monodentate approach through C(4)O, N(3) and imidazole ring N(3) atoms respectively. The thermogravimetric analysis shows the dehydration, decomposition and thermal stability of mixed ligand complexes. XRD and SEM patterns show sharp crystalline peaks with homogeneous morphology. In vitro antimicrobial activities of free ligands (A & B) and their metal complexes were screened against some pathogenic strains by well diffusion technique. Absorption and gel electrophoresis experiments on the interaction of mixed ligand complexes with DNA suggest that all the complexes can bind as well as cleave the DNA by intercalation between chromophores and DNA base pairs. In addition, in vitro antioxidant activities were tested by DPPH free radical scavenging model.
- Shobana, Sutha,Subramaniam, Perumal,Dharmaraja, Jeyapraksh,Narayan, Arvind
-
-
Read Online
- Nickel(II)?π interaction in [M(ampy)2Ni(μ-CN)2(CN)2]n (M = Zn(II) and Cd(II), ampy = 2-aminomethylpyridine): Syntheses, vibrational spectroscopy, thermal analyses and crystal structures of cyano-bridged heteronu
-
Two novel three-dimensional cyano-bridged heteronuclear polymeric complexes, [Zn(ampy)2Ni(μ-CN)2(CN)2]n (1) and [Cd(ampy)2Ni(μ-CN)2(CN)2]n (2), (ampy = 2-aminomethylpy
- Kürk?üo?lu, Güne? Süheyla,Ye?ilel, Okan Zafer,Kavlak, Ilkan,Büyükgüng?r, Orhan
-
-
Read Online
- Unprecedented interweaving of hetero-chiral single helical chains into a 3D chiral framework with (10, 3) topology
-
The title compound, [Ni(dcbp)(H2O)2](H2dcbp = 2,2′ -bipyridine-4,4′ -dicarboxy acid), was synthesized under hydrothermal conditions. The structure was determined by single-crystal X-ray diffraction and further characterized by elemental analysis, IR, and TGA. The compound crystallized in an orthorhombic system, P212121 space group, a = 6.7665(7) A, b = 12.9047(14) A, c = 13.1848(15) A, β = 90°. In the compound, each Ni(II) atom exhibits a six-coordinated distorted octahedral geometry. Interestingly, carboxylate group from dcbp ligands bridges between adjacent Ni(II) atoms giving rise to unprecedented interweaving of hetero-chiral single helical chains into a 3D chiral (10, 3) framework. Copyright Taylor & Francis Group, LLC.
- Zhang, Cui-Qiao,Fu, Feng,Li, Dong-Sheng,Ren, Yi-Xia,Zhao, Xin-Ze
-
-
Read Online
- Exfoliation-free nanosheet synthesis of transition-metal hydroxynitrate and its transformation to oxide particulate nanosheet
-
A new strategy, epoxide-assisted precipitation route presented in this work, allows the exfoliation-free nanosheet synthesis of Ni3(NO 3)2(OH)4 by the control of dynamics of the precipitation reaction. The mechanism of growth limitation in the third direction can be explained by the bonding of the molecule resulting from the ring-opening reaction of the epoxide to the surface of primary nanosheets, preventing the thickening of the layer. Copyright
- Cui, Hongtao,Zayat, Marcos,Levy, David
-
-
Read Online
- Spectroscopic studies and thermal decomposition for (bis-((E)-2-(4-ethylphenylimino)-1,2-diphenylethanone) Schiff base and its Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes prepared by direct and template reactions
-
A new Schiff base (bis-((E)-2-(4-ethylphenylimino)-1,2-diphenylethanone) containing four active coordination centers (ONNO) and its metal complexes have been synthesized and characterized by elemental analyses, spectroscopic methods, molar conductance, thermal and magnetic measurements. The tetrahedral and square planar trinuclear Co(II), Ni(II) and Cu(II) complexes (1–3), respectively, have been prepared by direct reaction, while the template reaction gives octahedral complexes (4–8) with different stoichiometries 3:1, 2:1, 1:1 (M:L). The ESR spectra of solid copper (II) complexes in powder form showed an axial symmetry with 2B1g as a ground state. The thermal decomposition mechanisms of metal complexes were studied. All the thermal decomposition processes ended with the formation of metal oxide. The thermal study showed that the complexes with different solvents of crystallization exercise different types of interaction. The kinetic and thermodynamic parameters have been calculated.
- Emam, Sanaa M.,AbouEl-Enein, Saeyda A.,Emara, Esam M.
-
-
Read Online
- Effect of operational key parameters on photocatalytic degradation of phenol using nano nickel oxide synthesized by sol-gel method
-
Photocatalytic oxidation of phenol was studied using nickel oxide (NiO) nanoparticles synthesized by sol-gel method. The morphology of synthesized catalyst was studied by using field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The average particle size was 6.5 nm as estimated by Scherrer formula and was confirmed by HRTEM and FESEM analysis. The photocatalytic activity of NiO was evaluated by degradation of phenol under irradiation of unique source like UV laser. The influence of various key parameters such as amount of photocatalyst, initial solution pH and the initial concentration of phenol was investigated. The operational parameters show the expected influence regarding the efficiency of the photocatalytic degradation process. The photocatalytic degradation efficiency of NiO was found to decrease with the increase in the initial solution pH. The degradation of the phenol followed a pseudo first-order rate kinetics with k = 5.7 × 10-2 min-1.
- Hayat, Khizar,Gondal,Khaled, Mazen M.,Ahmed, Shakeel
-
-
Read Online
- Hydrothermal synthesis, crystal structures, and properties of CoII and NiII supramolecular complexes with 2,4,6-trimethyl benzoate and 4,4′-bipyridyl
-
Two new coordination complexes, viz. [Co(tmb)2(4,4′-bpy)2(H2O)2](Htmb)2 (1) and {[Ni(tmb)2(μ-4,4′-bpy)2(H2O)2](4,4′-bpy)}n (2), have been hydrothermally synthesized by reaction of the corresponding metal acetate with 2,4,6-trimethylbenzoic acid (Htmb) and 4,4′-bipyridyl (4,4′-bpy). X-ray single-crystal diffraction suggests that complex 1 represents a discrete mononuclear species in which the central metal ion is coordinated by the terminal carboxylate moiety and the 4,4′-bipyridyl ligand. The crystal structure of complex 2 reveals a 1D chain coordination polymer in which the Ni(II) ions are connected by the bridging 4,4′-bipyridyl ligands. In both cases, the coordination arrays are further extended via hydrogen bonding interactions to generate 3D supramolecular networks. Complexes 1 and 2 have also been characterized by spectroscopic (IR and UV/Vis), thermal (TGA) and magnetic susceptibility measurements. In addition, both complexes exhibit antimicrobial activity.
- Indrani, Murugan,Ramasubramanian, Ramasamy,Kumaresan, Sudalaiandi,Kang, Sung Kwon,Chen, Min,Du, Miao
-
-
Read Online
- Preparation of nickel nanoparticles for catalytic applications
-
Spherical oxidized nickel particles 15 to 200 nm in average size have been produced by a crucibleless aerosol method involving metal vapor condensation in an inert gas flow and oxidation processes. The particles have been characterized by scanning electron microscopy, X-ray microanalysis, X-ray diffraction, BET surface area measurements, and vibrating-sample magnetometry. The process parameters have been optimized for the preparation of particles with tailored size, specific surface area, and saturation magnetization. A dc electric field applied to the condensation zone during the oxidation process reduces the size and increases the extent of oxidation of the particles. We have studied low-temperature oxidation of carbon monoxide and propane on nickel nanopowders differing in particle size and extent of oxidation. The nanoparticles with optimized characteristics have been shown to have a marked catalytic effect on these processes.
- Morozov, Yu. G.,Belousova,Kuznetsov
-
-
Read Online
- Thermal, spectral and magnetic behaviour of 2,3,4-trimethoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II)
-
Four new complexes of 2,3,4-trimethoxybenzoic acid anion with manganese(II), cobalt(II), nickel(II) and copper(II) cations were synthesized, analysed and characterized by standard chemical and physical methods. 2,3,4-Trimethoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II) are polycrystalline compounds with colours typical for M(II) ions. The carboxylate group in the anhydrous complexes of Mn(II), Co(II) and Ni(II) is monodentate and in that of Cu(II) monohydrate is bidentate bridging one. The anhydrous complexes of Mn(II), Co(II) and Ni(II) heated in air to 1273 K are stable up to 505-517 K. Next in the range of 505-1205 K they decompose to the following oxides: Mn3O4, CoO, NiO. The complex of Cu(II) is stable up to 390 K, and next in the range of 390-443 K it loses one molecule of water. The final product of its decomposition is CuO. The solubility in water at 293 K is of the order of 10-3 mol dm-3 for the Mn(II) complex and 10-4 mol dm-3 for Co(II), Ni(II) and Cu(II) complexes. The magnetic moment values of Mn2+, Co2+, Ni2+ and Cu2+ ions in 2,3,4-trimethoxybenzoates experimentally determined in the range of 77-300 K change from 5.64-6.57 μB (for Mn 2+), 4.73-5.17 μB (for Co2+), 3.26-3.35 μB (for Ni2+) and 0.27-1.42 μB (for Cu2+). 2,3,4-Trimethoxybenzoates of Mn(II), Co(II) and Ni(II) follow the Curie-Weiss law, whereas that of Cu(II) forms a dimer.
- Ferenc, Wieslawa,Bocian, Beata,Sarzynski
-
-
Read Online
- Thermal studies of Co(II), Ni(II) and Cu(II) complexes of N,N′-bis(3,5-Di-t-butylsalicylidene)ethylenediamine
-
The thermal decomposition kinetics of sterically hindered salen type ligand (L) and its metal complexes [M=Co(II), Ni(II), Cu(II)] were investigated by thermogravimetric analysis. A direct insertion probe-mass spectrometer (DIP-MS) was used for the charac
- Dogan,Ulusoy,Oeztuerk,Kaya,Salih
-
-
Read Online
- Kinetic and thermodynamics studies on the decompositions of Ni3C in different atmospheres
-
The thermal decompositions (including TG and DSC) of nickel carbide were studied under different atmospheres of Ar, air and H2. X-ray diffraction combined with element analysis indicated that nickel metal, together with solid amorphous carbon,
- Leng, Yonghua,Xie, Lei,Liao, Fuhui,Zheng, Jie,Li, Xingguo
-
-
Read Online
- Discharge-Induced Enhancement of the Oxygen Evolution Reaction
-
The fundamental understanding of the surface reconstruction induced by the applied potential is of great significance for enhancing the oxygen evolution reaction (OER). Here, we show that a previously overlooked discharge current in the low applied potential region also leads to in situ electrochemical activation of a nitrogen-doped nickel oxyhydroxide surface. We exploit the fact that doping of heteroatoms weakens the surface structure, and hence, a weak discharge current originating from the capacitive nature of nickel oxyhydroxide has a strong structure-reforming ability to promote the formation of nitrogen and oxygen vacancies. The current density at 1.4 V (vs. Hg/HgO) can dramatically increase by as much as 31.3 % after discharge in the low applied potential region. This work provides insight into in situ enhancement of the OER and suggests that the low applied potential region must be a primary consideration in evaluating the origin of the activity of electrocatalysts.
- Ge, Baoxin,Hao, Jinhui,Hou, Jianwen,Li, Longhua,Luo, Wei,Shi, Weidong,Wang, Shuaishuai,Yang, Wenshu,Zhao, Kun
-
-
Read Online
- A series of bis(pyridyl)-bis(amide)-modulated metal-1,2-phenylenediacetate coordination polymers: construction and selective dye adsorption
-
Five new coordination polymers (CPs), namely, [Cu(3-bpcb)(1,2-pda)]·2H2O (1), [Cu(4-bpah)(1,2-pda)(H2O)]·H2O (2), [Ni2(4-bpah)2(1,2-pda)2(μ2-H2O)] (3), [Cu3(4-bpfp)(1,2-pda)2(μ3-OH)2] (4), [Co(4-bpfp)0.5(1,2-pda)(H2O)] (5), were prepared by hydrothermal reactions of metal(ii) chloride with 1,2-H2pda (H2pda = 1,2-phenylenediacetic acid) in the presence of different bis(pyridyl)-bis(amide) ligands (3-bpcb = N,N′-bis(3-pyridinecarboxamide)-1,4-benzene; 4-bpah = N,N′-bis(4-pyridinecarboxamide)-1,2-cyclohexane; and 4-bpfp = N,N′-bis(4-pyridylformyl)piperazine) and structurally characterized by single crystal X-ray diffraction, infrared spectroscopy (IR), elemental analysis, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). Complexes 1-3 show three different 2D layers with diverse (42·67·8)(42·6), (44·62) and (42·6)(42·67·8) topological structures, respectively. Complex 4 exhibits a 3D polymeric framework, which presents a novel (3,4,8)-connected topology with the Schl?fli symbol (3·4·5)2(32·42·52·614·74·83·9)(32·63·7). Complex 5 displays a 3D network with 3,4-connected (42·63·8)(42·6) topology. The diverse arrangements of these complexes show the remarkable sensitivity of the metal(ii)-H2pda system to the different bis(pyridyl)-bis(amide) ligands. In addition, the electrochemical properties of complexes 3-5 and the dye adsorption properties of the title complexes are also discussed.
- Wang, Xiuli,Zhao, Jing,Le, Mao,Lin, Hongyan,Liu, Guocheng,Wang, Xiang
-
-
Read Online
- Self-assembled sandwich-like NiO film and its application for Li-ion batteries
-
NiO film with sandwich-like morphology is fabricated on nickel foam by a simple ammonia-evaporation process. Ammonia plays a major role in controlling the final geometry during this template- and surfactant-free synthesis. The obtained NiO film is constructed by regular triangular prisms with side length of 500 nm. Each triangular prism is self-assembled by single crystalline platelets. As an anode for lithium ion battery, this NiO film electrode exhibits high discharge capacity and excellent cycling performance. The reversible capacity of the sandwich-like NiO film sustains 400 mAh g-1 even after 50 cycles at 2 C, much higher than that of the dense NiO film prepared by eletrodeposition (198 mAh g-1). The high rate capability and reversibility of this NiO film can be attributed to its unique sandwich-like architecture.
- Zhong,Wang,Xia,Gu,Xiang,Zhang,Tu
-
-
Read Online
- 1D hydrogen-bonded infinite chains from tetraaza macrocycle nickel(II) complexes and ligands
-
The reaction of square planar complex [Ni(L2)]Cl2·2H2O (L2?=?3,14-diethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) with ligands KNCS and H2cpdc generates 1D hydrogen-bonded infinite chains [Ni(L2)(NCS)2] (1) and [Ni(L2)(H-cpdc)2] (2) (H2cpdc?=?cyclopropanedicarboxylic acid). These compounds have been characterized by X-ray crystallography, spectroscopic, cyclic voltammetry and thermogravimetry. The crystal structures of compounds 1 and 2 show that each nickel(II) centre has an elongated distorted octahedral geometry with the axial ligands. Electronic spectra and redox potentials of the complexes 1 and 2 exhibit a high-spin octahedral environment, which is reflected by the nature of the axial ligands. The TGA behaviors of two compounds 1 and 2 are also significantly affected by the nature of the axial ligands.
- Lim, In-Taek,Choi, Ki-Young
-
-
Read Online
- The role of thermal analysis in optimization of the electrochromic effect of nickel oxide thin films, prepared by the sol-gel method: Part II
-
Thin films and the corresponding xerogels were prepared from nickel acetate precursor using the sol-gel dip-coating technique. The differences in thermal stability of the two forms of samples were studied by dynamic and isothermal thermogravimetry. For th
- Cerc Koro?ec,Bukovec
-
-
Read Online
- Nb effect in the nickel oxide-catalyzed low-temperature oxidative dehydrogenation of ethane
-
A method for the preparation of NiO and Nb-NiO nanocomposites is developed, based on the slow oxidation of a nickel-rich Nb-Ni gel obtained in citric acid. The resulting materials have higher surface areas than those obtained by the classical evaporation method from nickel nitrate and ammonium niobium oxalate. These consist in NiO nanocrystallites (7-13 nm) associated, at Nb contents >3 at.%., with an amorphous thin layer (1-2 nm) of a niobium-rich mixed oxide with a structure similar to that of NiNb2O6. Unlike bulk nickel oxides, the activity of these nanooxides for low-temperature ethane oxidative dehydrogenation (ODH) has been related to their redox properties. In addition to limiting the size of NiO crystallites, the presence of the Nb-rich phase also inhibits NiO reducibility. At Nb content >5 at.%, Nb-NiO composites are thus less active for ethane ODH but more selective, indicating that the Nb-rich phase probably covers part of the unselective, non-stoichiometric, active oxygen species of NiO. This geometric effect is supported by high-resolution transmission electron microscopy observations. The close interaction between NiO and the thin Nb-rich mixed oxide layer, combined with possible restructuration of the nanocomposite under ODH conditions, leads to significant catalyst deactivation at high Nb loadings. Hence, the most efficient ODH catalysts obtained by this method are those containing 3-4 at.% Nb, which combine high activity, selectivity, and stability. The impact of the preparation method on the structural and catalytic properties of Nb-NiO nanocomposites suggests that further improvement in NiO-catalyzed ethane ODH can be expected upon optimization of the catalyst.
- Zhu, Haibo,Ould-Chikh, Samy,Anjum, Dalaver H.,Sun, Miao,Biausque, Gregory,Basset, Jean-Marie,Caps, Valerie
-
-
Read Online
- Porous NiO/Ag composite film for electrochemical capacitor application
-
A highly porous NiO/Ag composite film is prepared by the combination of chemical bath deposition and silver mirror reaction. The as-prepared NiO/Ag composite film has an interconnecting reticular morphology made up of NiO flakes with highly dispersed Ag nanoparticles of about 6 nm. The pseudocapacitive behavior of the NiO/Ag composite film is investigated by cyclic voltammograms (CV) and galvanostatic charge-discharge tests in 1 M KOH. The NiO/Ag composite film exhibits weaker polarization, higher specific capacitance and better cycling performance as compared to the unmodified porous NiO film. The specific capacitance of the porous NiO/Ag composite film is 330 F g-1 at 2 A g-1 and 281 F g-1 at 40 A g-1, respectively, much higher than that of the unmodified porous NiO film (261 F g-1 at 2 A g-1 and 191 F g-1 at 40 A g-1). The enhancement of pseudocapacitive properties is due to highly dispersed Ag nanoparticles in the composite film, which improves the electric conductivity of the film electrode.
- Wu,Li,Lin
-
-
Read Online
- HSAB principle and nickel(II) ion reactivity towards 1-methyhydantoin
-
1-Methylhydantoin and its novel nickel(II) complex [Ni(H2O) 4(1-mhyd)2] were prepared and identified, by elemental analysis, single crystal X-ray determination and MS methods. In addition, the complex was characterized by spectroscopic (IR, UV-Vis), magnetic and thermal techniques. The ligand reveals an interesting supramolecular architecture with both classical and non-conventional extended HB bonding networks. All rings and chains formed due to this HB bonding are embedded into the undulated pattern. A single crystal X-ray diffraction analysis of the complex shows that the nickel ion is coordinated by deprotonated hydantoin and water ligands in a N 2O4 tetragonal arrangement. In the [Ni(H 2O)4(1-mhyd)2] structure both inter and intramolecular hydrogen bonds are created with the participation of water molecules. The ESI-MS method confirmed mono-nuclearity of the complex while electronic spectroscopy proved the tetragonal and pseudooctahedral geometries around the metal ion in the solid state and solution, respectively. By application of the "average environment rule", 10Dq parameters were obtained for the hypothetical, hexa-coordinate [Ni(1-mhyd)6] approximation or rather more realistic [Ni(1-mhyd)3] chelate. Based on this the mhyd ligand was ranked in the spectrochemical series close to ammonia. The general consideration of the structure of the hydantoin complexes as a function of the metal ion hardness within the framework of the HSAB theory has been provided. Both the ligand and the complex were found to be non-toxic agents against breast (MCF-7), lung carcinoma epithelial (A549) and mouse fibroblasts (Balb/3T3) cancer cell lines.
- Puszyńska-Tuszkanow, Mariola,Daszkiewicz, Marek,Maciejewska, Gabriela,Staszak, Zbigniew,Wietrzyk, Joanna,Filip, Beata,Cie?lak-Golonka, Maria
-
-
Read Online
- Charge transporting enhancement of NiO photocathodes for p-type dye-sensitized solar cells
-
A p-type NiO film was prepared by doctor-blading of Ni(OH)2 paste onto FTO glass, followed by sintering at 450 °C for 30 min. The influence of nucleation condition of Ni(OH)2 on the morphology of NiO films and consequently charge transporting behavior is investigated. A smooth and compact NiO film is obtained with smaller Ni(OH)2 sol-gel particle size, which is confirmed by the surface topography examination. The hole transporting ability of NiO semiconductor is enhanced with such a compact film because of better interconnection between particles, as evidenced from electrochemical impedance analysis. The NiO film obtained is employed as the photocathode in p-type dye-sensitized solar cells (DSSCs) using arylamine-based dyes. The short-circuit photocurrent is two times improved to ca. 2.0 mA cm -2 compared to rough films.
- Hsu, Chih-Yu,Chen, Wei-Ting,Chen, Yung-Chung,Wei, Hung-Yu,Yen, Yung-Sheng,Huang, Kuan-Chieh,Ho, Kuo-Chuan,Chu, Chih-Wei,Lin, Jiann T.
-
-
Read Online
- Interfacial Electron Redistribution of Hydrangea-like NiO@Ni2P Heterogeneous Microspheres with Dual-Phase Synergy for High-Performance Lithium–Oxygen Battery
-
Lithium–oxygen batteries (LOBs) with ultra-high theoretical energy density (≈3500?Wh?kg?1) are considered as the most promising energy storage systems. However, the sluggish kinetics during the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) can induce large voltage hysteresis, inferior roundtrip efficiency and unsatisfactory cyclic stability. Herein, hydrangea-like NiO@Ni2P heterogeneous microspheres are elaborately designed as high-efficiency oxygen electrodes for LOBs. Benefitting from the interfacial electron redistribution on NiO@Ni2P heterostructure, the electronic structure can be modulated to ameliorate the chemisorption of the intermediates, which is confirmed by density functional theory (DFT) calculations and experimental characterizations. In addition, the interpenetration of the P-O bond at the NiO@Ni2P heterointerface leads to the internal doping effect, thereby boosting electron transfer to further improve ORR and OER activities. As a result, the NiO@Ni2P electrode shows a low overpotential of only 0.69?V, high specific capacity of 18254.1?mA?h?g?1 and superior long-term cycling stability of over 1400 h. The exploration of novel bifunctional electrocatalyst in this work provides a new solution for the practical application of LOBs.
- Li, Runjing,Ran, Zhiqun,Shu, Chaozhu,Wen, Xiaojuan,Xu, HaoYang,Yan, Yu,Zeng, Ting,Zhao, Chuan
-
-
- Synthesis, characterization, in vitro antimicrobial and cytotoxic evaluation of Co(II), Ni(II), Cu(II) and Zn(II) complexes derived from bidentate hydrazones
-
Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized from hydrazone ligands (HL1–HL4) obtained by condensation reaction of 6-chlorothiochroman-4-one with benz hydrazide/nicotinic hydrazide/isonicotinic hydrazide/p-toluic
- Devi, Jai,Kumar, Sanjeev,Kumar, Deepak,Jindal, Deepak Kumar,Poornachandra
-
p. 423 - 455
(2021/11/03)
-
- Nano-flower like NiO modified BiOBr composites with direct Z-scheme: Improved visible light degradation activity for dyes
-
Facing environmental pollution, the development of semiconductor photocatalysts with efficient electron-hole pairs separation is necessary for better performance optimization and utilization. Here, a direct Z-scheme BiOBr–NiO-x% (x ?= ?5, 10, 20, 30) photocatalysts with outstanding photocatalytic activity for dye degradation were prepared via the hydrothermal process. The XRD, XPS, FESEM, HRTEM and UV–vis DRS were used to characterize the components, phase structure, morphology and optical properties of the prepared samples. The prepared nano-flower like BiOBr–NiO-x% (x ?= ?5, 10, 20, 30) composites had an extensive visible light absorption range and more vigorous absorption intensity than pure BiOBr. All the prepared composites exhibited better photocatalytic activity for rhodamine (RhB) degradation than that of pure BiOBr, with BiOBr/NiO-20% showing the best photocatalytic efficiency. The photocatalytic efficiency had reached 98% within 50 ?min for the BiOBr/NiO-20% composite. Due to the tight interfacial contact and matching band positions between BiOBr and NiO, a direct Z-scheme BiOBr/NiO heterojunction was built, which accelerated the visible light absorption, superior separation of photoinduced electron-hole pairs in space and improved the oxidation and reduction capacity of the catalysts, further leading to the excellent photocatalytic activity for degradation of RhB.
- Li, Xuehui,Peng, Yujie,Tian, Tao,Wang, Dantong,Ren, Xiaozhen,Pu, Xipeng
-
-
- Structural characterization, spectroscopic studies, and molecular docking studies on metal complexes of new hexadentate cyclic peptide ligand
-
New cyclic peptide ligand (L), 4,7,17,20-tetrabenzyl-2,5,8,16,19,22-hexaoxo-3,6,9,15,18,21-hexaaza-1(1,3)-benzenacyclodocosaphane-10-carboxylic acid (BOABCA), was prepared using the recommended method. The ligand (L) and its complexes have been proven by
- Moustafa, Gaber,Sabry, Eman,Zayed, Ehab M.,Mohamed, Gehad G.
-
-
- Antibacterial and anticorrosion behavior of bioactive complexes of selected transition metal ions with new 2-acetylpyridine Schiff base
-
Successful preparation of Schiff base 4-(4-aminophenoxy)-N-(1-(pyridin-2-yl)ethylidene)aniline derived from refluxing of 4,4-oxydianniline with 2-acetylpyridine within 2?h in 1:1 molar ratio was performed. Different transition metal complexes were synthesized by reacting metal chlorides with the formed ligand in 1:1 molar ratio. Structural features of the complexes were obtained from different tools such as infrared (IR), 1H-nuclear magnetic resonance (1H-NMR), ultraviolet–visible (UV-vis), molar conductivity, thermogravimetric (TG)/differential thermogravimetric (DTG), microanalysis, and mass spectrometry. All complexes had an octahedral structure and Schiff base acted as a neutral bidentate ligand that linked to metal centers via N-azomethine and N-pyridine atoms. Cr(III), Fe(III), and Ni(II) complexes were electrolytes while other complexes were nonelectrolytes. The molecular structure of Schiff base was optimized theoretically and its HOMO and LUMO energies were dictated by B3LYP/DFT calculations. The in vitro antibacterial activity versus some selected bacteria species showed that all prepared compounds were biologically active except Fe(III) complex against certain species and Co(II) complex had the highest biological activity values. Molecular docking was used to determine effective binding modes between ligand and its [Co(L)(H2O)2Cl2]·4H2O complex with active sites of 4WJ3, 4ME7, 4K3V, and 3T88 receptors. The strongest binding of Co(II) complex was with the 4ME7 receptor with lowest binding energy value ?25.4?kcal mol?1. Schiff base as corrosion inhibitors for mild steel in 1.0-M HCl had been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PP), and electrochemical frequency modulation (EFM). The results showed that the inhibitor acts as a mixed-type inhibitor. The inhibition efficiency increases with increasing inhibitor concentration to its maximum of 97.5% at 1?×?10?3?M solution. The adsorption model obeys the Langmuir isotherm, and Gibbs free energy was around ?40 kJ/mol, indicating that it is spontaneously and chemically adsorbed on the surface. SEM/EDX results proved the sticking of a barrier film on the mild steel sample.
- Ashmawy, Ashraf M.,Deghadi, Reem G.,Elsharkawy, Ahmed E.,Mohamed, Gehad G.
-
-
- Study of Sn doped NiO microwires with waveguiding behaviour grown by a vapor-solid process
-
Sn-doped NiO microwires with tailored structure of defects, optical properties and waveguiding behaviour were fabricated by a one-step vapor-solid method. The presence of metallic Sn or SnO2 in the precursor mixture favours the formation of elongated microstructures with singular morphologies. This geometry, not explored so far, provides an increased surface to volume ratio and a characteristic morphology, which is of potential interest in a wide range of surface properties and optoelectronic functionalities. In this work, the structural, compositional, electronic and optical properties of the microwires have been analyzed as a function of Sn precursor. Depending on the employed Sn precursor, the optical properties such as their luminescence or waveguiding behaviour can be tailored. In some of the analysed microwires a red laser can be guided along the microstructure. This behaviour has not been previously reported for NiO so far, hence increasing the functionality and applicability of this material.
- Cremades, A.,Maestre, D.,Tae?o, M.
-
-
- Platinum Modulates Redox Properties and 5-Hydroxymethylfurfural Adsorption Kinetics of Ni(OH)2 for Biomass Upgrading
-
Nickel hydroxide (Ni(OH)2) is a promising electrocatalyst for the 5-hydroxymethylfurfural oxidation reaction (HMFOR) and the dehydronated intermediates Ni(OH)O species are proved to be active sites for HMFOR. In this study, Ni(OH)2 is modified by platinum to adjust the electronic structure and the current density of HMFOR improves 8.2 times at the Pt/Ni(OH)2 electrode compared with that on Ni(OH)2 electrode. Operando methods reveal that the introduction of Pt optimized the redox property of Ni(OH)2 and accelerate the formation of Ni(OH)O during the catalytic process. Theoretical studies demonstrate that the enhanced Ni(OH)O formation kinetics originates from the reduced dehydrogenation energy of Ni(OH)2. The product analysis and transition state simulation prove that the Pt also reduces adsorption energy of HMF with optimized adsorption behavior as Pt can act as the adsorption site of HMF. Overall, this work here provides a strategy to design an efficient and universal nickel-based catalyst for HMF electro-oxidation, which can also be extended to other Ni-based catalysts such as Ni(HCO3)2 and NiO.
- Chen, Wei,Li, Yingying,Liu, Jilei,Lu, Yuxuan,Song, Minglei,Wang, Shuangyin,Wang, Yanyong,Wu, Yujie,Zhou, Bo,Zhou, Wang,Zou, Yuqin
-
supporting information
p. 22908 - 22914
(2021/09/16)
-
- Roles of highly ordered mesoporous structures of Fe-Ni bimetal oxides for an enhanced high-temperature water-gas shift reaction activity
-
Highly ordered mesoporous Fe-Ni bimetal oxide (m-FeNi) catalysts synthesized using KIT-6 as a hard-template by a nanocasting method were investigated for an alternative high-temperature water-gas shift (HT-WGS) reaction. The as-synthesized m-FeNi at an optimal Ni/Fe ratio of 0.24 revealed significantly enhanced activity and stability with high CO2 selectivity and small methanation activity, which were attributed to the well-dispersed Ni nanoparticles in Fe2O3-NiO frameworks caused by altering the reducibility of Fe nanoparticles. The contributions of Ni nanoparticles were found not only to enhance the reducibility of active FeOx species but also to increase the interaction of Fe2O3-NiO interfaces, and were responsible for the less aggregation of Fe nanoparticles and smaller coke depositions. The newly formed stronger interactions between the mesoporous Fe2O3 and highly dispersed NiO nanoparticles at their optimal amounts were responsible for the superior structural and catalytic stability of alternative m-FeNi metal oxides even under HT-WGS reaction conditions.
- Bae, Jong Wook,Cho, Jae Min,Han, Gui Young,Park, Yong Min
-
p. 3251 - 3260
(2021/05/26)
-
- MOF-derived NiWO4@NiO p-p heterostructure for distinguish detection of TEA and xylene by temperature regulation
-
Accurate detection of outdoor air quality requires a large number of gas sensors to be used in various fields. Thus, it is greatly significance to develop multifunctional sensors. In this work, the NiWO4 decorated NiO p-p type heterostructure were successfully synthesized using the metal organic framework (MOF) as a self-sacrificing template with annealing process. The gas sensitive measurements reveal that the 12 wt% NiWO4 decorated NiO based sensor exhibits the higher response value (65) than that of the pure NiO sensor (2.5) to 50 ppm triethylamine (TEA) at 240 °C. The selectivity of the NiWO4 decorated NiO based sensors could be changed when the operating temperature over 260 °C, and the 12 wt% NiWO4 decorated NiO based sensor shows the higher response value (28) than that of the pure NiO sensor (2) to 50 ppm xylene at 270 °C, indicated that as-prepared the NiWO4 decorated NiO heterostructure can be as a promising material applied to fabricate the dual sensor to detect TEA and xylene with high sensitivity as well as distinguish by adjusting the temperature. The improved gas-sensing mechanisms of the NiWO4 decorated NiO based on sensor are discussed in detail.
- Wang, Dongxue,Gu, Kuikun,Zhang, Jing,Xing, Dejun,Zhang, Mingzhe
-
-
- A novel selective oxidative cleavage of C–C bond mediated by black nickel oxide in the presence of molecular oxygen
-
A selective aerobic oxidative cleavage of C–C bond is developed with black nickel oxide (NiOx) as the catalyst. For the oxidation of 1-phenyl-1, 2-ethanediol, a 97.5% conversion in 96.7% selectivity of benzaldehyde is obtained under 0.3 MPa of O2 at 140 °C for 3 h. The relationship between the catalytic performance of NiOx and structure is discussed. It is concluded that the existence of Ni3+ should be crucial to the activity of catalyst. Moreover, the recycling experiments showed that the catalyst can retain a high activity even after being reused for five times.
- Meng, Lingwu,Li, Wei,Guo, Pengfei,Wang, Shun,Tong, Xinli
-
-
- Co (II), Cu (II), Mn (II), Ni (II), Pd (II), and Pt (II) complexes of bidentate Schiff base ligand: Synthesis, crystal structure, and acute toxicity evaluation
-
5-methoxy-2-(((2chloro-5-(trifluoromethyl)phenyl)imino)methyl)phenol) (HL) and its cobalt (II), copper (II), manganese (II), nickel (II), palladium (II), and platinum (II) complexes, [Co(L)2]·4H2O (1), [Cu(L)2] (2), [Mn(L)
- Lupa?cu, Gina,Pahon?u, Elena,Shova, Sergiu,B?rbuceanu, ?tefania Felicia,Badea, Mihaela,Paraschivescu, Codru?a,Neam?u, Johny,Dinu, Mihaela,Ancuceanu, Robert Viorel,Dr?g?nescu, Doina,Dinu-P?rvu, Cristina Elena
-
-
- Transition metal complexes derived from 2-hydroxy-4-(p-tolyldiazenyl)benzylidene)-2-(p-tolylamino)acetohydrazide synthesis, structural characterization, and biological activities
-
Mononuclear Cu(II), Ni(II), Co(II), Mn(II), Zn(II), Fe(III), Ru(III), and UO2(II) complexes of 2-hydroxy-4-(ptolyldiazenyl) benzylidene)-2-(p-tolylamino)acetohydrazide (H2L) were prepared by direct method. The ligand and its complexes were isolated in sol
- Abdu, Ashwaq M.,Al-Fakeh, Maged S.,Alhagri, Ibrahim A.,Alhakimi, Ahmed N.,Saeed, S. El-Sayed,Shakdofa, Adel M. E.,Shakdofa, Mohamad M. E.
-
-
- New Mn(II), Co(II), Ni(II) and Cu(II) homoleptic complexes with 6-chloro-5-7-dimethyl-4oxo-4H-chromene-3-carbaldehydes and its heteroleptic complexes with quinoline-8 ol: synthesis, characterization and antimicrobial activity
-
In the present study, the synthesis of ligand 6-chloro-5-7-dimethyl-4oxo-4H-chromene-3-carbaldehydes by three steps from the substituted phenol. The formed product in the first step was further processed by fries rearrangement reaction and subsequently Vilsmeier–Haack reaction. Then, its homoleptic and heteroleptic complexes with Mn(II), Co(II), Ni(II) and Cu(II) metal ions by using second ligand quinolin-8-ol were synthesized. The ligand and complexes were characterized by different techniques, such as electron dispersive spectroscopy and elemental analysis (CHN), Fourier transform infrared (FTIR), electronic spectroscopy and magnetic susceptibility, 1H-Nuclear magnetic resonance spectroscopy and mass spectra of ligand, electron spin resonance (ESR), thermogravimetric analysis, powder X-ray diffraction, scanning electron microscopy (SEM) and molar conductivity. The spectroscopic analysis like NMR and the FTIR shows that the both ligands are bidentate in nature. The UV–visible spectra show the homoleptic complex of Cu(II) shows square planer, while M = Ni(II), Co(II) and Mn(II) shows octahedral in nature. While the complexes with heteroleptic ligands from square planer geometry with Cu(II) and Ni(II) while Co(II) and Mn(II) show octahedral geometries. The geometry was also supported by magnetic susceptibility and FTIR spectra. The ESR spectra of Cu(II) complexes shows both are square planer geometry and the G-value was more than 4 indicating the absence of exchange interaction between Cu(II) metal ions in the solid state. The powder X-ray diffraction was used to determine the crystal system of all the complexes, while supporting to this X-ray diffraction the SEM was also taken for the nanostructure of complexes was developed or not. Then, the solution state conductivity of the complexes shows electrolytic in nature. Further, these complexes were evaluated for its antimicrobial activity by agar well diffusion method and structure–activity relationship. The ligands show antimicrobial activity against S.typhi. The Ni(II) does not show antibacterial activity, while complexes Cu(II), Co(II) and Mn(II) shows good activity against the gram-positive and the gram-negative bacteria. The heteroleptic ligand complex (6) of Cu(II) shows higher antifungal activity as compared with Ni(II), Co(II) and Mn(II) complexes.
- Kolhe, Nitin H.,Jadhav, Shridhar S.,Thube, Dilip R.,Takate, Sushma J.,Bankar, Ashok V.,Moharekar, Sanjay T.,Pawar, Hari R.,Moharekar, Shubhangi S.
-
p. 459 - 481
(2020/10/13)
-
- Heteroligand bivalent transition metal complexes with an azo-oxime ligand and 1,10-phenanthroline: Synthesis, spectroscopy, thermal analysis, DFT calculations and SOD-mimetic activities
-
Novel mononuclear heteroligand transition metal complexes: [M(HL)(phen)2]ClO4, (M: Mn(II) for 1, Ni(II) for 2), [M(HL)(phen)(ClO4)], (Ni(II) for 3, Cu(II) for 4, Zn(II) for 5) with 2-[(E)-(hydroxyimino)methyl]-4-[(E)-pheny
- Serbest, Kerim,Dural, Turan,Emirik, Mustafa,Zengin, Ali,Faiz, ?zlem
-
-
- Nickel nanoparticle/carbon catalysts derived from a novel aqueous-synthesized metal-organic framework for nitroarene reduction
-
Carbon-supported, non-noble metal-based catalysts derived from metal-organic frameworks (MOFs) are attractive alternatives to noble metal-based systems, but typical syntheses of the starting MOFs are not desirable from an environmental and practical perspective (e.g., they rely on non-innocuous organic solvents and long reaction times). Here, we report the preparation of a Ni-based MOF in aqueous medium, at moderate temperature (95 °C) and in a short reaction time (2 g?1 depending on the carbonization temperature applied to the MOF, as well as high Ni contents (between ~36 and 57 wt%). Notwithstanding the latter, the metal was homogeneously distributed throughout the carbon matrix in the hybrid and was quite resistant to extensive agglomeration and sintering, even at temperatures as high as 1000 °C. With increasing carbonization temperature, the Ni component was seen to go through different crystal phases, i.e., Ni3C phase → Ni hexagonal close-packed phase → Ni face-centered cubic phase. The results of the catalytic tests suggested the former and latter phases to be the most active towards the reduction of 4-NP, with catalytic activity values as high as 0.039 mol4-NP molNi?1 min?1.
- Martín-Jimeno, F. Julian,Martínez-Alonso, Amelia,Paredes, Juan I.,Suárez-García, Fabián,Tascón, Juan M. D.
-
-
- In situ synthesis of Ag/NiO derived from hetero-metallic MOF for supercapacitor application
-
Nanocomposite metal oxides have been attracted great attention in the electrode material of supercapacitor. Herein, a novel Ag/Ni hetero-metallic complex with the hamburger-like structure was prepared, which was then calcined to form Ag/NiO nanocomposite via in-situ preparation. The in-situ formed Ag/NiO exhibits a very high capacitance of 1480 F g ?1 at a current density of 0.6 A g?1 in 1?M KOH solution, and the cycling stability was retained about 85% after 3000 cycles with the current of 5 A g?1. The results showed that the in-situ formed Ag/NiO derived from hetero-metallic MOF possess high specific capacitance, which could provide a new effective strategy to improve the conductivity of metal oxides nanocomposite.
- Zhou, Lin-Xia,Yang, Yuan-Yuan,Zhu, Hong-Lin,Zheng, Yue-Qing
-
p. 1795 - 1807
(2020/11/30)
-
- Design, synthesis, DFT studiesand anticancer activity of novel metal complexes containing 1,3,5-triazino[1,2-a]benzimidazole moiety using microwave as an approach for green chemistry
-
2-(2-amino-4,10-dihydrobenzo[4,5]imidazo[1,2-a][1,3,5]triazin-4-yl)phenol (ligand)and its related metal complexes of Mn (II), Co (II), Ni (II), Cu (II) and Zn (II)were prepared under microwave irradiation. The structures of prepared compounds were elucidated in terms of elemental analysis, FT-IR, UV-Vis, 1HNMR, 13CNMR, EPR spectra and mass spectra in addition to magnetic studies at room temperature and thermal properties. Elemental analysis results determined mole ratios between the ligand and metal 1:1 or 1:2. The microwave approach provides clean, shorter reaction times and enhancements in yields. Coats Redfern and Horowitz Metzger equation were used to study Thermal kinetic parameters of dehydration and decomposition of the complexes.The geometries of the ligand and its Mn (II), Co (II),Cu (II) and Zn (II) complexes were optimized using Gaussian 09 W; density functional theory (DFT) B3LYP method. Also, the cytotoxic activity of the ligand and its metal complexes were evaluated against liver cancer cells (HepG-2) and the Cu (II) complex exhibited the highest cytotoxic activity with promising IC50 value = 3.5μg/mlcompared to standard referencecisplatin.
- Hassan, Ali M.,Heakal, Bassem H.,Khamis, Hamdy,El-Naeem, Gamal Abd,Marzouk, Emad,Abdelmoaz, Miral A.,Younis, Ahmed
-
p. 323 - 340
(2021/01/18)
-
- Study molecular modeling and the effect of some biological metals on the efficiency of norfloxacin in presence of 3-(bromoacetyl)coumarin
-
A series of new mixed ligand metal complexes of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized by the reaction of norfloxacin (NOR) with 3-(bromoacetyl)coumarin (BAC) in 1:1:1 (Mn+:NOR:BAC) molar ratio, which characterized by elemental analysis, spectroscopic measurements (FT-IR, UV–Vis) molar conductance, effective magnetic moments, and thermogravimetric analysis (TG) and (DTG). All the complexes soluble in DMSO and the conductivity measurement indicate that the complexes are electrolyte with ratio 1:1 for Mn(II), Fe(II), and Zn(II) and 1:2 for Co(II), Ni(II), and Cu(II). Electronic and magnetic data elucidated the octahedral structure for all complexes. Assorted thermodynamic factors are calculated, and the results are explicated. Molecular modeling calculations (bond angles, dihedral angles, total energy, heat of formation, and dipole moment) confirm the structural geometry of the complexes and indicate the very good agreement between the computed and experimental geometrical parameters. The calculated data for the hardness (η) and absolute softness (σ) showed that all complexes are soft with respect to ligands. The two ligands and their metal complexes have also been screened for their antibacterial and antifungal activity against some selected species; the data showed that the complexes have remarkable potency as compared with the parent ligands.
- El-Shwiniy, Walaa H.,Gamil, Manar A.,Sadeek, Sadeek A.,Zordok, Wael A.
-
-
- Ru3+, Mn2+, Co2+, Ni2+, Cu2+, and Zn2+ uni-metallic complexes of 3-(-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) methylene) hydrazono)indolin-2-one, preparation, structure elucidation and antibacterial activity
-
Ru3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+ uni-metallic complexes of dihydrazone derived from the condensation of 3-hydrazonoindolin-2-one with 4-formyl antipyrine were synthesized. The resulted dihydrazone and its chelated compounds structurally characterized basing on spectroscopic tools (NMR, FT-IR, EAS, ESI-MS) thermo-gravimetric, elemental, magnetic and molar conductance measurements. This structural elucidation leads us to conclude that the dihydrazone has been performed as a neutral bidentate chelator linked the Ru3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+ ions via the carbonyl and azomethine of isatin moiety adopting regular or distorted octahedral structures around the central metallic ions. The structural description of dihydrazone and its chelated compounds have been endorsed basing on the Density Functional Theory calculations. The optimized geometry, global reactivity descriptors, and LUMO-HOMO orbitals and of the molecules have been calculated by the DFT-B3LYP method and 6e311G(d,p) basis set. The molecular electrostatic potential picture has been painted utilizing the same level of theory to envision the molecules charge distribution and chemical reactivity. The DFT studies of the designated compounds revealed small HOMO-LUMO gap which is a strong indication to the large reactivity these compounds. The TG analysis has confirmed the complexes chemical formulae and assured that the thermo-degradation processes occur in three or four steps ended with the formation of metal oxide or carbon-contaminated metal oxide residues. The In-vitro antibacterial of dihydrazone and its chelated compounds have been evaluated against E. coli, P. aeruginosa, K. pneumonia and B. subtilis, the observed antibacterial result denoted that Cu2+ and Zn2+ complexes have a good activity in comparation with the free dihydrazone.
- Selim, Quad M.,Shakdofa, Adel M. E.,Shakdofa, Mohamad M. E.
-
-
- Transition metal (II) complexes of hydrazones derived from tetralone: synthesis, spectral characterization, in vitro antimicrobial and cytotoxic studies
-
Abstract: A series of transition metal (II) complexes with general formula [M(L1?4)2(H2O)2] (where M = Co(II), Ni(II), Cu(II) and Zn(II)) was synthesized by the reaction of metal(II) acetates with hydrazones [HL1–HL4] obtained from condensation of tetralone with hydrazide derivatives. The characterization of synthesized compounds (1–20) was done by using elemental analysis, different spectral studies (UV–Vis, 1H NMR, 13C NMR, FT-IR, mass, ESR and fluorescence), magnetic susceptibility, molar conductance measurement and thermal (DTA, TGA and DTG) analysis. The characterization results suggested the bidentate nature of the hydrazones, which chelate with the metal ion via nitrogen of (C=N) group and deprotonated carbonyl oxygen in the enolized form, resulting in stable, non-volatile octahedral complexes. The antimicrobial potential of the compounds was evaluated against four bacterial, i.e. (S. aureus, B. subtilis, P. aeruginosa and E. coli), and two fungal species, i.e. (A. niger and C. albicans), by a serial dilution method with complexes 15 and 16 as most active compounds against microbes. All the compounds were also tested for its cytotoxicity (in vitro) against three human cancer cell lines (A549, HeLa and MCF-7) and one normal cell line (L6) by the MTT assay, which focussed on an increased activity of compounds 7 and 15 towards A549, MCF-7 and HeLa cancer cell line with IC50 values ranging from 10.76 to 16.42?μg/mL, and compounds were found to be non-toxic towards L6 cell line as compared to the standard drug doxorubicin. The results demonstrated that complexation enhanced the biological activity of compounds. Graphic abstract: The synthesized compounds (1–20) were screened for antitumor activities against A549, MCF7, Hela cancer cell lines. Copper complex (7) and (15) was found to be the most active antitumor agent and less toxic against L6—Rat myoblast normal cell line than standard doxorubicin.[Figure not available: see fulltext.].
- Devi,Sharma,Kumar,Jindal,Dutta,Kumar
-
p. 2433 - 2467
(2021/03/04)
-
- Multi-sensing response, molecular docking, and anticancer activity of donor–acceptor chalcone containing phenanthrene and thiophene moieties
-
Donor–Acceptor (D–π–A) chalcone containing phenanthrene and keto-thiophenly moieties, abbreviated as PhTPO, was synthesized and characterized. The solvatochromic effect was investigated in different solvents of various polarities. The absorption and fluorescence spectra have shown bathochromic shifts from non-polar to polar solvents due to intramolecular charge transfer interactions. The fluorescence characteristics (fluorescence intensity, fluorescence maxima, and energy) of PhTPO are highly sensitive to the polarity of the solvents compared to the corresponding absorption spectra. In addition, the inclusion characteristic of PhTPO in different organized assemblies was studied. The spectral changes suggested that PhTPO would be useful to study the microenviromental polarity and evaluation of critical micelle concentrations of the studied surfactants. Reversible acidochromic behavior was observed after addition of H2SO4/NaOH with a significant color change. Further, the optical sensing response towards H+, Co2+, Ni2+, Pb2+ and Cd2+ ions was investigated. Also, it responds well to the tested metal ions as reflected from the changes in both the absorption and emission spectra upon adding different concentrations of the metal salts. The solid complexes of PhTPO with Co2+, Ni2+, Pb2+ and Cd2+ were then synthesized and characterized. Depending on the magnetic moments results, the geometric structures were found to be octahedral and tetrahedral for paramagnetic Co2+, and Ni2+ complexes, respectively, while they are diamagnetic for Pb2+ and Cd2+ complexes. Moreover, the geometry of PhTPO and its complexes were confirmed by the density functional theory (DFT) using DMOL3 program. The binding affinity towards the epidermal growth factor receptor (EGFR) protein was also investigated by the Molecular Operating Environment (MOE) software. The anticancer activity was then evaluated against four different cell lines using MTT assay. The results suggest that the investigated PhTPO would be potential candidate for solvents polarity sensors, as a probe to characterize critical micelle concentrations of surfactants, and sensor for the studied metal ions and H+ proton. In addition, [PhTPO–Ni2+] and [PhTPO–Co2+] complexes are good candidate for further antitumor activities studies owing to their potent cytotoxic and anticancer activities compared to the Pb2+ and Cd2+ complexes.
- El-Nahass, Marwa N.,Fayed, Tarek A.,Elazim, Saleh Abd,El-Gamil, Mohammed M.,Draz, Doaa F.,Hassan, Fathy
-
-
- Impact of Mg and Ti doping in O3 type NaNi1/2Mn1/2O2on reversibility and phase transition during electrochemical Na intercalation
-
O3 type layered sodium nickel manganese oxide, NaNi1/2Mn1/2O2, which is isostructural with α-NaFeO2, has attracted attention as a promising positive electrode material for sodium-ion batteries owing to its large reversible capacity of ca. 200 mA h g-1. To improve the cycle stability for practical use, O3 type NaNi1/2Mn1/2O2 materials with Mg or/and Ti substitution are synthesized. The materials with Mg or Ti substitution exhibit better capacity capability, and Mg and Ti co-substituted material demonstrates even better capacity capability, with an initial discharge capacity of 200 mA h g-1 without any capacity loss due to substitution. Substitution of Mg2+ and Ti4+, which are larger ions than Ni2+ or Mn4+, results in a larger in-plane lattice of the O3 type structure, in contrast to the shrinkage during charging, and this has the potential to delay the phase transition during charging. In contrast to the non-substituted NaNi1/2Mn1/2O2, the Mg and Ti co-substituted material demonstrates more continuous phase transitions and lattice parameter changes, and no significant shrinkage of the interslab spacing in the layered structure, as evidenced by ex situ and operando X-ray diffraction. The coexistence of Mg and Ti enhances not only the reversibility of the structural change but also the structural stability at the surface, resulting in the excellent sodium battery performance. This journal is
- Fujitani, Naoya,Komaba, Shinichi,Kubota, Kei,Kuroki, Kazutoshi,Tokita, Yusuke,Yoda, Yusuke
-
p. 12830 - 12844
(2021/06/16)
-
- Synthesis, characterization and biological studies of a sterically hindered symmetrical nitrogen donor ligand and its metal complexes
-
A new sterically hindered Schiff base ligand (SN-NNDMB) was synthesized from meso-1,2-diphenyl ethylenediamine (meso-stien) and 4-N,N′-dimethylaminobenzaldehyde. Its structure was determined by single-crystal X-ray diffraction data. The crystal structure of the organic ligand was found to be triclinic, space group P-1 with a = 6.1407(8) ?, b = 8.8372(12) ?, c = 12.0006(15) ?, α = 103.882(7)°, β = 95.325(8)°, γ = 91.082(7)°, F(0 0 0) = 254, Dc = 1.253 Mg/m3, μ = 0.571 mm?1, R = 0.0399, and wR = 0.1019. Co, Ni, Cu and Zn complexes of SN-NNDMB were also prepared and characterized by elemental analysis, IR-, mass-, NMR- and electronic- spectra, magnetic moment, molar conductance, powder XRD, and TGA. The obtained results show that the Schiff base ligand acts as a bidentate, coordinated through the azomethine nitrogen atoms. According to the biotest such as Antimicrobial, DNA binding, DNA cleaving, Anti-tubercular, Anticancer, and SOD-like activity, the compounds showed better activity after chelation. The Cu(II)-SN-NNDMB complex showed the highest bioactive potential amonst the analyzed compounds.
- Arish, D.,Bhuvanesh, N.,Kumaresan, S.,Shiju, C.
-
-
- Syntheses, characterization and oxygen evolution reaction (OER) electrocatalytic properties of M(II) based bromo-salophen complexes
-
Efficient oxygen evolution reaction catalyst can be prepared via controlled decomposition method, and there is still minimal mechanistic understanding of such method. Here, we introduce a 3-Bromo-salophen ligated nickel(II) and copper(II) complexes as a precursor to obtain a Ni and Cu-based oxygen evolution reaction electrocatalyst via the controlled decomposed method. In our case, the unique O,N chelation mode of the 3-Bromo-salophen ligand (bis[2-bromosalicylydene]-1,2-iminophenylenediamine) was used to synthesize M(II) complexes. By regulating the decomposition conditions, we successfully obtained varied structures. The designing of a nonprecious, highly efficient and long-lasting oxygen evolution reaction electrocatalyst for electrochemical water splitting is a current emergency for reducing energy demand in the future. In this study, we found cost-effective decomposed products of NiO and CuO which are prepared by a simple one-step chemical precipitate method at high temperature (500 °C). The chemical composition, structure and morphology of the decomposed products NiO and CuO were confirmed by PXRD, FTIR and SEM spectroscopy. The decomposed products were loaded onto a glassy carbon electrode by a drop-casting method. For the oxygen evolution reaction, the complexes as well as their decomposed products, NiO and CuO achieve an ultralow over-potential exhibit onset lower potential 1.5 V in 0.1 M KOH solution.
- Gautam, Chiteri,Kumar, Pramod,Sharma, Vinod Kumar,Singh, Anar,Singh, Ashish Kumar,Singh, Ayushi
-
-
- Structural, electrical, and magnetic properties of bulk Nd1-xSrxNiO3 (x = 0–0.3)
-
The single-phase Nd1-xSrxNiO3 (x = 0–0.3) polycrystalline samples were successfully synthesized, and the structure, resistivity, and magnetic property were investigated. All of samples were well indexed to an orthorhombic structure with Pnma space group. With increasing Sr concentration x, the lattice parameter a decreased, the lattice parameter b and c increased, the obtained unit-cell volume systematically increased due to the larger ion radius of Sr2+ than Nd3+. Sr partial substitution for Nd suppressed the metal-insulator and antiferromagnetic transition until x = 0.2. However, as the Sr content increased to 0.3, some abnormal phenomena were observed. The present work shows that physical properties are correlated with the evolution of perovskite tolerance factor in Nd1-xSrxNiO3 system.
- Chen, Yongliang,Cui, Yajing,Shu, Jun,Wen, Zhiwei,Yang, Hongwei,Zhao, Yong
-
-
- Synthesis, Structure, and Electrical Properties of New Homo and Heteronuclear Schiff Base Copper(II) and Nickel(II) Complexes
-
Abstract: In this study, the new Schiff base ligands N,N′-bis[(1Z,2E)-1-(4-methylphenyl)-2-(hydroxyimino)-1-phenylethylidene]-4-methylbenzene-1,2-diamineand N,N′-bis[(1Z,2E)-1-(4-chlorophenyl)-2-(hydroxyimino)ethylidene]-4-methylbenzene-1,2diamine have be
- Bulut, D. Takanoglu,Karap?nar, E.,Karap?nar, N.,Topal, T.
-
p. 1117 - 1122
(2021/08/06)
-
- Spectroscopic studies, DFT calculations, thermal analysis, anti-cancer evaluation of new metal complexes of 2-hydroxy-N-(4-phenylthiazol-2-yl)benzamide
-
2-Hydroxy-N-(4-phenylthiazol-2-yl)benzamide was reacted with Cr(III), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Ag(I) metal ions to synthesize the corresponding coordination compounds. From the study, 2-hydroxy-N-(4-phenylthiazol-2-yl)benzamide was rearranged to 2-hydroxy-N-(4-phenyl-1,3-thiazole-2-yl)carboxymidic acid (HL) due to the keto-enol tautomeric forms, where the enol form is more dominant. The structures of the HL ligand and the newly synthesized coordination compounds have been characterized by elemental analysis, IR, UV-Visible, 1H NMR, ESR and mass spectral data, in addition to thermal gravimetric analysis (TGA) and magnetic and molar conductance measurements. The ligand behaves as a monobasic bidentate ON sites, where the bidentate binding of the ligand involving the phenolic oxygen and azomethine nitrogen. The binding modes of the coordination compounds were further confirmed using Gaussian 09 software. The complexes of Co(II), Cu(II), Zn(II), and Ag(I) were tested in vitro against human colon carcinoma cells (HCT-116). The IC50 values showed dramatic toxicity results for cobalt(II), copper(II) and zinc(II) complexes versus human colon carcinoma (HCT-116) cell line, compared to African green monkey kidney (VERO) normal cell line. According to the results of the IC50 values obtained for Co(II), Cu(II), Zn(II), and Ag(I) 1.5, 1.0, 1.8 and 7.3 μg/ml, respectively, compared to the reference drug (2.49 μg/ml), Co(II), Cu(II), Zn(II) compounds are considered strong antitumor agent while Ag(I) compound can be considered as a weak one. For both antifungal and antibacterial activities, HL and all its coordination compounds were evaluated. HL ligand has only high activity against B. subtilis and C. albicans while Co(II) and Zn(II) compounds have the highest activity against S. aureus, P. aeruginisa, B. subtilis and E. coli.
- Emara, Adel A. A.,Mahmoud, Nelly H.,Rizk, Mariam G.
-
-
- Synthesis, characterization, biological evaluation, and molecular docking approach of nickel (II) complexes containing O, N-donor chelation pattern of sulfonamide-based Schiff bases
-
A series of Schiff bases (L1–L4) that possess in their structure bioactive sulfonamide group and their nickel (II) complexes have been synthesized. Microanalytical analyses, various spectroscopic methods such as Fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance (NMR), 13C NMR, UV–Vis, and MS, are used to explore the nature of bonding and to elucidate the chemical structures. The analytical and magnetic values suggest a range of stoichiometries 1:1, 1:2, and 2:1 (M:L) for the synthesized complexes of almost square planar geometry. The spectral comparative interpretation reveals that L1 and L2 coordinate to the central Ni (II) in tetradentate ONON donor sequence, whereas L3 and L4 in bidentate ON pattern through deprotonated phenolic-O and the azomethine-N. Density functional theory (DFT) and MOE-docking approaches are used to evaluate the molecular parameters and the binding propensity of the synthesized ligands and their complexes with 3s7s protein and to signify their inhibition strength. Besides, the anticancer, antimicrobial and antifungal activities have been screened against number of tumor cells and human pathogen strains. These in vitro studies reveal that Schiff base L4 and its complex, [Ni(L4-H)(OAc)(H2O)], have superior activities reflecting the importance of inserting bioactive pendant substituents such as thiazole ring and 3-fluorophenylazo to the pharmacophoric sulfonamide moiety. Moreover, some of the synthesized Ni (II) complexes display promising therapeutic effects as novel non-platinum antitumor agents after further preclinical investigations.
- Ramadan, Ahmed M.,Bayoumi, Hoda A.,Elsamra, Rehab M. I.
-
-
- Preparation of NiO/WO3 Heterostructure and Photocatalytic Properties in Removal of Lincomycin Antibiotic: Experimental Study and Molecular Dynamic Simulation
-
Abstract: The aim of this study was to evaluate the efficiency of NiO/WO3 heterostructure photocatalytic process for removal of lincomycin antibiotic from aqueous solutions. WO3, NiO, and NiO/WO3 particles were synthesized
- Fazaeli, R.,Ghorbani, M. H.,Khamani, S.,Khodadadi, Z.,Torkian, L.
-
p. 2154 - 2162
(2021/10/06)
-
- Synthesis, structural characterization, density functional theory calculations, and antimicrobial, anticancer, and antimetastatic properties of nanosized heteroleptic complexes of cocaine/TMEDA with d-block metal ions
-
In the field of transition metal chemistry, the development of transition metal-based drugs for the treatment of diseases such as cancer or microbial infections with minimization of adverse effects and drug resistance constitutes an active area of research. Herein, eight novel nanosized heteroleptic complexes of cocaine/TMEDA with the formula [M(COC)(TMEDA)Cly(OH2)z]nCl·xH2O (M = Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II); COC = cocaine; TMEDA = N,N,N′,N′-tetramethylethylenediamine, y = 1–2; z = 0–1; n = 0–1; and x = 0–2) were synthesized and structurally characterized via elemental analysis, molar conductivity, mass spectrometry, and spectroscopic and microscopic techniques. The thermal properties and kinetic thermodynamic parameters of the synthesized complexes were also studied. The geometry and electronic structures were investigated via density functional theory (DFT) calculations. The antiproliferative activity of the complexes on HepG-2 and MCF-7 cancer cell lines was quantified via MTT assay. The Fe(III) and Cd(II) complexes exhibited promising cytotoxic activities against the HepG-2 and MCF-7 cancer cell lines, respectively, with minimum effect on HFB4 human normal cells. Further molecular mechanistic studies were performed on the Cd(II) complex to inspect its influence on different cancer pathophysiology-related processes in the MCF-7 cell line including metastasis, apoptosis, and cellular oxidative stress and on the cellular levels of the human tumor suppressor nuclear proteins p21 and p27. The results revealed that the Cd(II) complex is a promising anticancer agent that acts through several molecular mechanisms with minimum effect on the normal cells and with additional antimetastatic properties. Furthermore, the antibacterial and antifungal activities of the prepared complexes were investigated.
- Abdallah, Abanoub Mosaad,Zaki, Nadia G.,Mahmoud, Walaa H.,El Kerdawy, Ahmed M.,Mohamed, Gehad G.
-
-
- Adsorption of methylene blue onto synthesized Co3O4, NiO, CuO and ZnO nanoparticles
-
The metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) with glutamine were synthesized and characterized by elemental analyses, IR, electronic spectra, thermal analyses (TGA and DTA), nuclear magnetic resonance (1H and 13CNMR), ele
- Dossoki, Farid I. El,Hosny, Nasser Mohammed,Rady, Sarah
-
-
- Metal complexes of Tridentate Schiff base: Synthesis, Characterization, Biological Activity and Molecular Docking Studies with COVID-19 Protein Receptor
-
Mononuclear chelates of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II) and Cd(II) resulted from new tridentate Schiff base ligand, 4-((1-(5-acetyl-2,4-dihydroxyphenyl)ethylidene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, were synthesized. Metal
- Mohamed, Gehad G.,Omar,Ahmed, Yasmin M.
-
p. 2201 - 2218
(2021/10/14)
-
- CO-ORDINATION BEHAVIOUR of HYDRAZINE and ISOMERS of ACETOXY BENZOIC ACIDS with TRANSITION METAL IONS
-
New hydrazine complexes of some divalent transition metal ions of formulae, [M{(2-ab)2(N2H4)}].3H2O, [M{(3-ab)2(N2H4)}].3H2O and [M{(4-ab)2(N2H4)2}].2H2O where M = Co, Ni, Zn and Cd; 2-abH = 2-acetoxy benzoic acid, 3-abH = 3-acetoxy benzoic acid and 4-abH
- Bai, E. Helen Pricilla,Vairam, S.
-
p. 337 - 350
(2022/01/03)
-
- Synthesis, Structure, DFT, and Biological Activity of Metal Complexes of Norfloxacin and Metformin Mixed Ligand
-
Abstract: A new series of mixed ligand metal complexes has been synthesized by the reaction of Co(II), Ni(II), Cu(II), Zr(IV), Pd(II), and Cd(II) with norfloxacin (NOR) and metformin hydrochloride (MF) in 1 : 1 : 1 molar ratio. The complexes have been characterized by FT-IR, UV-Vis, and 1H NMR spectra, TG/DTG and elemental analysis, molar conductance, and magnetic susceptibility data. According to FT-IR, NOR chelates with metal ions as a bidentate ligand via one oxygen of the carboxylate group and pyridone oxygen, and MF chelates with metal ions via two imine groups. Complexes have been identified as electrolytes. Electronic and magnetic data have indicated the octahedral structure for all complexes except square planar Pd(II) complex. Antibacterial and antifungal activities of the compounds have been tested against several species, and have indicated higher inhibition against micro-organisms for the metal complexes than the mixed ligands.
- Abbass, L. M.,El-Shwiniy, W. H.,El-Telbany, M.,Sadeek, S. A.,Zordok, W. A.
-
p. 1774 - 1782
(2021/11/01)
-
- Aerobic epoxidation of olefins by carboxylate ligand-based cobalt (II) compound: synthesis, X-ray crystallography, and catalytic exploration
-
A new quinoline carboxylate-based cobalt (II) metal compound, [Co (HL1)2(H2O)4] (1) (H2L1 = 2-hydroxyquinoline-4-carboxylic acid) has been hydrothermally synthesized, and fully characterized by single-crystal X-ray diffraction, powder X-ray diffraction, Fourier-transform infrared (FT-IR), elemental and thermo-gravimetric analysis. Compound 1 shows high thermal stability up to ~300°C. Single-crystal X-ray diffraction study of 1 exhibited monomeric structure experiences further stabilized in solid state through different non-covalent interaction, for example, H-bonding and π···π stacking interaction and extended to 3D supramolecular H-bonded network. Compound 1 efficiently catalyzes epoxidation reactions of olefins under homogeneous conditions using molecular oxygen as an oxidizer. Another reported quinoline carboxylate-based nickel (II) monomer [Ni(L2)2(H2O)2] (2) (HL2 = thiazole-4-carboxylic acid) has been synthesized and characterized to compare it with compound 1 towards aerobic epoxidation reactions, where 1 comes as superior.
- Brandao, Paula,Debnath, Rakesh,Gayen, Saikat,Ghosh, Pameli,Koner, Subratanath,Lin, Zhi,Maity, Tanmay,Mal, Dasarath,Patra, Birendra Nath,Pratihar, Jahar Lal,Sepay, Nayim
-
-
- Nickel oxide regulating surface oxygen to promote formaldehyde oxidation on manganese oxide catalysts
-
Catalytic oxidation is the most effective method to eliminate in-door formaldehyde, and Mn-based catalysts with low cost and high activity have drawn great attention for this reaction. Herein, p-type semiconductor NiO doped MnOx catalysts were prepared by an environmentally friendly oxalate co-precipitation method. The doped Ni species entered the lattice of MnOx to form amorphous Ni-Mn composite oxide/NiO and increased the ratio of surface Mn4+ and total amount of surface active oxygen simultaneously with the increase of NiO content in the form of a volcano curve, which directly correlated to the abilities for adsorption and oxidation of formaldehyde. Among them, 0.2NiO-MnOx (Ni/(Ni + Mn) = 0.2) showed the highest activity, 300 ppm of formaldehyde can be completely eliminated at 98 °C in a 2.5 vol% H2O-containing atmosphere, and the corresponding specific reaction rate was about 2.9 times higher than that of pure MnOx. Meanwhile, the enhanced migration of oxygen species over NiO-MnOx catalysts also promoted the replenishment of surface active oxygen that was consumed in the reaction process, which kept the activity of 0.2NiO-MnOx stable during the continuous reaction cycles and 26 h long-term stability test. Our study showed that utilizing NiO to regulate the reactivity and amount of surface oxygen species was an efficient way to improve the intrinsic catalytic performance of MnOx. This journal is
- Cui, Yao,Guo, Yanglong,Guo, Yun,Li, Zengyuan,Liu, Hao,Tang, Jie,Wang, Li,Yang, Jie,Zhan, Wangcheng,Zhao, Hailin
-
p. 7110 - 7124
(2021/11/17)
-
- Synergistic effect between La-Ni bimetallic oxides for the efficient decomposition of hydrogen peroxide
-
La-Ni bimetallic oxides, including LaNiO3 and La2NiO4, were prepared by a facile co-precipitation process, followed by calcination treatment. The formation process of these two La-Ni bimetallic oxides was traced by X-ray diffraction, and the calcination temperature was determined to have a crucial influence on the composition and crystalline structure of the final sample. These as-prepared La-Ni bimetallic oxides were used as catalysts for the decomposition of hydrogen peroxide. Benefiting from the synergistic effect between La and Ni, these La-Ni bimetallic oxides showed superior catalytic ability than the single-components oxides such as La2O3, Ni2O3, and NiO. Additionally, the La-Ni bimetallic oxides exhibited efficient catalytic activity after reusing them several times, showing a desirable cyclic performance. Moreover, the kinetics of the reaction was investigated. The activation energy of this reaction significantly decreased under the catalysis from the as-prepared La-Ni bimetallic oxides, further confirming the promising catalytic potential of these La-Ni bimetallic oxides. This journal is
- Liu, Kui,Cheng, Yafei,Shi, Ying,Zhang, Wei,Wang, Yu,Tang, Fan,Lin, Xijie
-
p. 1584 - 1589
(2021/02/03)
-
- Ligational and biological studies of Fe(III), Co(II), Ni(II), Cu(II), and Zr(IV) complexes with carbamazepine as antiepileptic drug
-
Carbamazepine (CBZ) is considered to be the preferred drug for fractional seizures and may also use in the prevention of primary generalized tonic–clonic seizures. The chelates of CBZ with Fe(III), Co(II), Ni(II), Cu(II), and Zr(IV) were designed and characterized on the basis of elemental analysis, FT-IR, 1H NMR, UV-visible, mass spectra, thermal analysis (TG, DTG, and DTA), molar conductivity, and magnetic moment. IR spectra emphasize that CBZ acts as a neutral bidentate ligand with metal ions through amide oxygen and amino nitrogen. UV-visible spectra and magnetic moment demonstrate that all chelates have geometric octahedral structures. Complexes thermal behavior is systematically analyzed employing TG and DTA technicality. TG findings signalize that water molecules (hydrated and coordinated) are extracted the first and second phases, while CBZ ligand is splitted in the second and subsequent steps. From the DTA curves, the obtained data reflect that the degradation processes are endothermic or exothermic peaks. Assorted thermodynamic factors are calculated, and the results are explicated. Antimicrobial activity was examined against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeuroginosa). Anti-fungal efficacy of the compounds has been tested. The Co(II) complex was highly significant against the antifungal Candida albicans and significantly against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis.
- Mohamed, Amira A.,Sadeek, Sadeek A.
-
-
- Self-assembled Ni/NiO impregnated polyaniline nanoarchitectures: A robust bifunctional catalyst for nitrophenol reduction and epinephrine detection
-
It is extremely significant to address an urgency toward the development of low-cost and efficient catalysts. Herein, for the first time, we synthesize a novel self-assembled Ni/NiO@PANI by a combustible crystallization followed polymerization method, constructed by impregnation of Ni/NiO in sulfonic acid-doped polyaniline, which can be used as a bifunctional catalyst for electrochemical sensing of epinephrine (EP) and reduction of nitro- to amino-phenol (4-NP to 4-AP). Due to the unique nanoarchitecture, ferromagnetic feature of Ni, anti-corrosion feature of PANI, and synergy between the system (metal/metaloxide@carbon) leads superior performance: it can rapidly reduce the 4-NP pollutant to environmentally friendly 4-AP within 8 min, and easy magnetic recycling; Also, it can be used as a sensor for EP neurotransmitters with a sensitivity, detection, and quantification limit of 0.117 nAμM?1, 87.2, and 290.71 μM, respectively. This work provides a strategy to design low-cost and superior catalysts applied in catalysis and electrochemical sensor.
- Ramadoss, Manigandan,Chen, Yuanfu,Ranganathan, Suresh,Giribabu, Krishnan,Thangavelu, Dhanasekaran,Annamalai, Padmanaban,Vengidusamy, Narayanan
-
-
- Structural elucidation, molecular modeling, and biological and antioxidant studies of phenanthroline/nicotinamide metals complexes
-
Three new cobalt (II), nickel (II), and copper (II) complexes [M (nicotinamide)(phenanthroline)(H2O)3]Cl2·3H2O (where M: Co (II), Ni (II) and Cu (II)) have been prepared and characterized by elemental analysis,
- El-Shwiniy, Walaa H.,Elwahed, Mohamed G. Abd,Saeed, Reham M.,Zordok, Wael A.,El-Desoky, Sameh I.
-
-
- Elucidation for coordination features of hydrazide ligand under influence of variable anions in bivalent transition metal salts; green synthesis, biological activity confirmed by in-silico approaches
-
Synthesis of new N′- cyclohexylidene-3?hydroxy-2-naphthohydrazide (H2L) complexes was carried out by ball milling technique in the lack of solvent (green approach) and then characterized by analytical and spectroscopic techniques. The metal salts used for preparations, were varied in their conjugated anions (Cl?, SO4?2 & OAc?) to investigate the changes in properties of obtained complexes, by changing anions, even with the same ligand. The ligand was coordinated mainly as monobasic with the metal acetate salts, while a neutral with metal chloride or sulfate salts. Such coordination modes were appeared through bidentate or tridentate towards central metals within different molar ratios (1: 1 or 1:2, M:L). Conductometric study was performed for Co(II) complex to estimate the complex stoichiometry and either formation or association constants, in solution state. DMOL3 program was used via DFT/B3LYP method to optimize the studied compounds and to obtain essential quantum parameters. Consequently, we confirmed the coordination of O(11), O(13) and N(16) atoms according to their features appeared in molecular modeling study. In-silico assessment was performed to examine the interaction features of new compounds with pathogenic-DNA, before in-vitro screening. Such assessment was carried out firstly by pharmacophore query within MolPort drug-library to discover the analogues drugs in activity towards DNA proteins. MolPort-007–588–377 and MolPort -000–734–772 were the code numbers of two analogues drugs. Secondly MOE-docking process was executed to explain all interaction features and rank the inhibition activity of complexes. Furthermore, antimicrobial, antioxidant and antitumor activity were investigated for all compounds and Ni(II)-Bis(HL) complex showed excellent antioxidant activity. Whereas, Co(II)-Bis(HL) complex showed excellent cytotoxicity towards liver cancer cells. Finally, the whole characteristics of complexes were changed by changing conjugated anions, even with the same ligand.
- Alkhamis, Kholood,Alkhatib, Fatmah,Alsoliemy, Amerah,Alrefaei, Abdulmajeed F.,Katouah, Hanadi A.,Osman, Hanan E.,Mersal, Gaber A.M.,Zaky, Rania,El-Metwaly, Nashwa M.
-
-
- Utilization and simulation of innovative new binuclear Co(ii), Ni(ii), Cu(ii), and Zn(ii) diimine Schiff base complexes in sterilization and coronavirus resistance (Covid-19)
-
This article aimed at the synthesis and molecular docking assessment of new diimine Schiff base ligand, namely 2-((E)-(2-((Z)-2-(4-chlorophenyl)-2-hydroxyvinyl)hydrazono) methyl)-6-methoxyphenol (methoxy-diim), via the condensation of 1-(4-chloro-phenyl)-2-hydrazino-ethenol compound with 2-((E)-(2-((Z)-2-(4-chlorophenyl)-2-hydroxy vinyl) hydrazono)methyl)-6-methoxyphenol in acetic acid as well as the preparation of new binuclear complexes of Co(ii), Ni(ii), Cu(ii), and Zn(ii). The following synthesized complexes were prepared in a ratio of 2:1 (metal/ligand). The 1H-NMR, UV-Vis, and FTIR spectroscopic data; molar conductivity measurements; and microanalytical, XRD, TGA/DTG, and biological studies were carried out to determine the molecular structure of these complexes. According to the spectroscopic analysis, the two central metal ions were coordinated with the diamine ligand via the nitrogen of the hydrazine and oxygen of the hydroxyl groups for the first metal ions and via the nitrogen of the hydrazine and oxygen of the phenol group for the second metal ions. Molecular docking for the free ligand was carried out against the breast cancer 3hb5-oxidoreductase and the 4o1v-protein binding kidney cancer and COVID-19 protease, and good results were obtained.
- Alam, Kehkashan,Alsanie, Walaa F.,Gaber, Ahmed,Kobeasy, Mohamed I.,Refat, Moamen S.,Zakaria, Rozan
-
p. 772 - 784
(2021/07/13)
-
- Synthesis, spectroscopic, theoretical and biological evaluation of novel Schiff base complexes of divalent transition metals
-
In the present manuscript, a new series of triazole-based Schiff base, (E)-4-((3-fluoro-4-methoxybenzylidene)amino)-5-propyl-4H-1,2,4-triazole-3-thiol (FMBT) and its metal complexes with divalent cobalt, nickel, copper, zinc and palladium are prepared and investigated for biological activities. The structural assignments of all the synthesized ligand and its metal complexes were done using different spectral methods like mass, infrared (IR), 1H-NMR, elemental analysis, electron spin resonance (ESR) and ultraviolet (UV)–visible. The magnetic properties, fluorescence profile and redox (cyclic voltammetry) behaviour of all the complexes were also investigated. Based on the spectral studies, the octahedral (Co[II], Ni[II] and Zn[II]) and square planar (Cu[II] and Pd[II]) structural environment have been proposed to the metal complexes. The results obtained from thermal and IR data confirmed the presence of coordinated water in metal complexes. The conductance measurements confirmed the non-electrolytic nature of metal complexes. Density functional theory (DFT)-based methods were used to ascertain the stability and chemical inertness of the compounds. Various electrostatic properties were also investigated by utilising the value of energy associated with different frontier molecular orbitals. The decomposition behaviour and stability of all the metal complexes was established from different thermodynamical functions calculated using Coats–Redfern method. The bio-efficacy of bidentate ligand and its complexes was evaluated against a wide spectrum of microbial cultures using Broths dilution method. Among the novel metal complexes Ni (1:2) (minimum inhibitory concentration [MIC] = 62.5?μg ml?1), Cu (1:1) (MIC = 62.5?μg ml?1) and Zn (1:2) (MIC = 12.5?μg ml?1) complexes were found to be more potent against Escherichia coli than the standard drugs.
- Singh, Kiran,Siwach, Preeti
-
-
- Dual-Site-Mediated Hydrogenation Catalysis on Pd/NiO: Selective Biomass Transformation and Maintenance of Catalytic Activity at Low Pd Loading
-
Creating a new chemical ecosystem based on platform chemicals derived from waste biomass has significant challenges: catalysts need to be able to convert these highly functionalized molecules to specific target chemicals and they need to be economical - not relying on large quantities of precious metals - and maintain activity over many cycles. Herein, we demonstrate how Pd/NiO is able to direct the selectivity of furfural hydrogenation and maintain performance at low Pd loading by a unique dual-site mechanism. Sol-immobilization was used to prepare 1 wt % Pd nanoparticles supported on NiO and TiO2, with the Pd/NiO catalyst showing enhanced activity with a significantly different selectivity profile; Pd/NiO favors tetrahydrofurfuryl alcohol (72%), whereas Pd/TiO2 produces furfuryl alcohol as the major product (68%). Density functional theory studies evidenced significant differences on the adsorption of furfural on both NiO and Pd surfaces. On the basis of this observation we hypothesized that the role of Pd was to dissociate hydrogen, with the NiO surface adsorbing furfural. This dual-site hydrogenation mechanism was supported by comparing the performance of 0.1 wt % Pd/NiO and 0.1 wt % Pd/TiO2. In this study, the 0.1 and 1 wt % Pd/NiO catalysts had comparable activities, whereas there was a 10-fold reduction in performance for 0.1 wt % Pd/TiO2. When TiO2 is used as the support, the Pd nanoparticles are responsible for both hydrogen dissociation and furfural adsorption and the activity is strongly correlated with the effective metal surface area. This work has significant implications for the upgrading of bioderived feedstocks, suggesting alternative ways for promoting selective transformations and reducing the reliance on precious metals.
- Botton, Gianluigi A.,Campisi, Sebastiano,Chan-Thaw, Carine E.,Chinchilla, Lidia E.,Chutia, Arunabhiram,Dimitratos, Nikolaos,Mohammed, Khaled M. H.,Villa, Alberto,Wells, Peter P.
-
p. 5483 - 5492
(2020/09/02)
-
- Anthraquinone Redox Relay for Dye-Sensitized Photo-electrochemical H2O2 Production
-
Anthraquinone (AQ) redox mediators are introduced to metal-free organic dye sensitized photo-electrochemical cells (DSPECs) for the generation of H2O2. Instead of directly reducing O2 to produce H2O2, visible-light-driven AQ reduction occurs in the DSPEC and the following autooxidation with O2 allows H2O2 accumulation and AQ regeneration. In an aqueous electrolyte, under 1 sun conditions, a water-soluble AQ salt is employed with the highest photocurrent of up to 0.4 mA cm?2 and near-quantitative faradaic efficiency for producing H2O2. In a non-aqueous electrolyte, under 1 sun illumination, an organic-soluble AQ is applied and the photocurrent reaches 1.8 mA cm?2 with faradaic efficiency up to 95 % for H2O2 production. This AQ-relay DSPEC exhibits the highest photocurrent so far in non-aqueous electrolytes for H2O2 production and excellent acid stability in aqueous electrolytes, thus providing a practical and efficient strategy for visible-light-driven H2O2 production.
- Sun, Jiaonan,Wu, Yiying
-
supporting information
p. 10904 - 10908
(2020/05/04)
-
- Facile synthesis of spray pyrolyzed ZnO/NiO nanocomposites thin films
-
This study reviews ZnO, NiO, and ZnO/NiO nanocomposites thin films deposition using the Spray Pyrolysis Technique (S.P.T). The thin films were deposited onto ordinary glass substrates heated at 500 °C from aqueous solutions of zinc chloride and nickel chl
- Antar, Bouhank,Youcef, Bellal
-
p. 895 - 900
(2020/10/02)
-
- Photocatalysis, photoinduced enhanced anti-bacterial functions and development of a selective: M-tolyl hydrazine sensor based on mixed Ag·NiMn2O4nanomaterials
-
In this work, a tri-metal based nanocomposite was synthesized and characterized. A detailed investigation of the photocatalytic dye degradation efficiency of the nanocomposite under visible light showed promising results in a wide pH range, both acidic and basic medium. Studies on anti-bacterial activity against seven pathogenic bacteria, including both Gram positive and Gram negative species, were conducted in the presence and absence of light and compared with the standard antibiotic gentamicin. The minimum inhibitory concentration (MIC) values of Ag·NiMn2O4 against multidrug-resistant (MDR) pathogens ranged from 0.008 to 0.65 μg μL-1, while the minimum bactericidal concentration (MBC) was found to be 0.0016 μg μL-1. The nanomaterial, Ag·NiMn2O4 was deposited onto the surface of a glassy carbon electrode (GCE; 0.0316 cm2) as a thin film to fabricate the chemical sensor probe. The proposed sensor showed linear current (vs. concentration) response to m-THyd (m-tolyl hydrazine) from 1.0 pM to 0.01 mM, which is denoted as the linear dynamic range (LDR). The estimated sensitivity and detection limit of the m-THyd sensor were found to be 47.275 μA μM-1 cm-2 and 0.97 ± 0.05 pM, respectively. As a potential sensor, it is reliable due to its good reproducibility, rapid response, higher sensitivity, working stability for long duration and efficiency in the analysis of real environmental samples.
- Al-Mamun, Mohammad,Alam, M. M.,Asiri, Abdullah M.,Azad, A. K.,Chandra Saha, Pallab,Hossain, Md Anwar,Rahman, Mohammed M.,Raihan, Topu,Rifat, Tanjila Parvin,Subhan, Md Abdus
-
p. 30603 - 30619
(2020/10/23)
-
- Methane Decomposition Nickel Catalysts Based on Structured Supports
-
Abstract: New methane degradation nickel catalysts based on original and modified layered double hydroxides and multilayer carbon nanotubes have been synthesized. The synthesized systems have been characterized by a set of physicochemical methods, namely, X-ray diffraction (XRD) analysis, scanning electron microscopy, Raman spectroscopy, and the thermal method. The catalytic activity of the synthesized catalysts in the temperature range of 550–850°С has been studied. It has been shown that in the methane decomposition reaction, the sample with a modified Ni-containing layer exhibits two regions of catalytic activity (550–650 and 700–850°С), whereas the sample based on carbon nanotubes is characterized by a single region (700–850°С) and the system based on a layered double hydroxide does not show activity in the entire temperature range.
- Gubanov, M. A.,Ivantsov, M. I.,Knyazeva, M. I.,Kryuchkov, V. A.,Kulikov, A. B.,Kulikova, M. V.,Maksimov, A. L.,Nikitchenko, N. V.,Pimenov, A. A.
-
p. 1043 - 1051
(2020/10/02)
-