- Synthesis and the crystal structure of CeCuS2
-
Single phase of CeCuS2 has been prepared by the mixture of CeO2 and Cu2S at 1000 ° C in CS2/Ar atmosphere. All X-ray diffraction peaks of CeCuS2 are indexed on the basis of the monoclinic system (space group: P21c) the same as LaCuS 2 and NdCuS2. The lattice parameters obtained by Rietveld analysis are a=0.6573(1) nm, b=0.7256(1) nm, c=0.6875(1) nm, and β=98.566(1)°.
- Komatsuzaki,Takase,Smura,Takahashi,Takano,Sekizawa,Clarke
-
-
Read Online
- Growth of bi-partite and metallic copper whiskers
-
Conditions for the growth of metallic copper and bi-partite whiskers of copper and cuprous sulphide are described with particular emphasis on the physical chemistry of the growth process. The mechanism of growth is explained and the significance of phase
- Jha,Grieveson
-
-
Read Online
- CuS nanostructures prepared by a hydrothermal method
-
Without using any surfactant or template, novel CuS three-dimensional (3D) structures consisting of nanosheets were successfully synthesized via a convenient one-step hydrothermal approach. X-ray diffraction pattern showed that the as-prepared product was pure hexagonal phase CuS. Scanning electron microscopy and high-resolution transmission electron microscopy images revealed that the as-prepared product comprised 3D microspheres (about 1-3 μm in diameter), which were further constructed with randomly oriented, single-crystalline CuS nanosheets (about 20 nm in thickness). The UV-vis absorption spectrum of the as-synthesized CuS 3D microspheres displayed an optical absorption minimum near 672 nm. Besides, the thermal stability of the as-synthesized CuS 3D microspheres was also studied.
- Huang, Qing-Li,Chen, Hu,Zhang, Yong Cai,Le Wu, Chang
-
-
Read Online
- Phosphine stabilized copper(i) complexes of dithiocarbamates and xanthates and their decomposition pathways
-
Phosphine stabilized compounds [Cu(i)(S2CNEt2)PR 3]2 (1-3) (R = OMe, Me and Et, respectively) and [Cu(i)(S2COEt)PR3]2 (4, 5), (R = OMe, and Me, respectively) have been prepared and characterised. The structures of compounds (1-3) were determined by X-ray single crystallography. The structures of all three compounds are based on centro-symmetric dimers which crystallise in the monoclinic space group P21/n with two [Cu(i)(S2CNEt 2)PR3]2 molecules per unit cell. The thermal decomposition of selected complexes was investigated by thermogravimetric, differential scanning calorimetry and gas chromatography with mass spectroscopy to understand the possible decomposition pathways.
- Afzaal, Mohammad,Rosenberg, Chico L.,Malik, Mohammad A.,White, Andrew J. P.,O'Brien, Paul
-
-
Read Online
- Synergistic Effect of Chemical Substitution and Insertion on the Thermoelectric Performance of Cu26V2Ge6S32Colusite
-
Copper-based sulfides are promising materials for thermoelectric applications, which can convert waste heat into electricity. This study reports the enhanced thermoelectric performance of Cu26V2Ge6S32 colusite via substitution of antimony (Sb) for germanium (Ge) and introduction of copper (Cu) as an interstitial atom. The crystal structure of the solid solutions and Cu-rich compounds were analyzed by powder X-ray diffraction and scanning transmission electron microscopy. Both chemical approaches decrease the hole carrier concentration, which leads to a reduction in the electronic thermal conductivity while keeping the thermoelectric power factor at a high value. Furthermore, the interstitial Cu atoms act as phonon scatterers, thereby decreasing the lattice thermal conductivity. The combined effects increase the dimensionless thermoelectric figure of merit ZT from 0.3 (Cu26V2Ge6S32) to 0.8 (Cu29V2Ge5SbS32) at 673 K.
- Shimizu, Yuta,Suekuni, Koichiro,Saito, Hikaru,Lemoine, Pierric,Guilmeau, Emmanuel,Raveau, Bernard,Chetty, Raju,Ohta, Michihiro,Takabatake, Toshiro,Ohtaki, Michitaka
-
-
Read Online
- Sonochemical preparation of copper sulfides with different phases in aqueous solutions
-
There is a growing interest in the synthesis of nanostructured copper sulfides due to their ability to form compounds with various stoichiometries. We report a sonochemical route for the preparation of copper sulfides with different compositions in aqueous solutions, using different, general and convenient copper sources such as copper acetate, copper hydroxide or basic copper carbonate and thiourea or thioacetamide as sulfur precursors under ambient air. Phase analysis, purity and morphology of the products were studied by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The results revealed that nanoparticles of covellite, CuS, with crystallite sizes between 7 and 18 nm can be obtained by using different precursors and complexing agents and that chalcocite, Cu 2S, can also be prepared sonochemically.
- Kristl, Matja?,Hojnik, Nu?a,Gyergyek, Sa?o,Drofenik, Miha
-
-
Read Online
- Field emission from crystalline copper sulphide nanowire arrays
-
Straight crystalline copper sulphide (Cu2S) nanowire arrays have been grown by using a simple gas-solid reaction at room temperature. These were demonstrated to exhibit semiconductor properties. Field emission was observed at a field of ～6MV/m, and its current-field characteristics deviate from Fowler-Nordheim theory, i.e., showing a nonlinear Fowler-Nordheim plot. The uniform emission from the whole arrays was observed using transparent anode technique, and their variation with applied field was recorded. The emission from individual nanowires was also studied using a field emission microscope, and was found to consist of a number of spatially resolved diffuse spots. Finally, stable emission current at different levels and over time was recorded. These findings indicate that semiconductor nanowires as cold cathode have a potential future, worthy of further comprehensive investigation. The technical importance of using semiconductor nanowires as cold cathode emitter is given.
- Chen, Jun,Deng,Xu,Wang, Suhua,Wen, Xiaogang,Yang, Shihe,Yang, Chunlei,Wang, Jiannong,Ge, Weikun
-
-
Read Online
- Effect of Precursor Mixture Composition on the Phase Composition and Electrical Transport Properties of Cu1.85ZnSnS4 and Cu1.5Zn1.15Sn0.85S4 Kesterite Solid Solutions Prepared in Molten KI
-
We have studied the effect of precursor mixture composition on the phase composition and electrical transport properties of Cu1.85ZnSnS4 and Cu1.5Zn1.15Sn0.85S4 solid solutions with the kes
- Gapanovich,Agapkin,Odin,Rakitin,Sedlovets,Kolesnikova,Novikov
-
-
Read Online
- Hydrothermal synthesis of transition-metal sulfide dendrites or microspheres with functional imidazolium salt
-
A series of transition-metal sulfide (PbS, CdS, ZnS, CoS, Cu2S) compounds were successfully synthesized through a facile hydrothermal method using 1-butyl-3-methlyimidazole thiocyanate ([BMIM][SCN]) as both sulfur source and capping ligand. The resultant products were characterized by X-ray powder diffraction (XRD) measurements in order to determine the crystalline phase of the products. The structural and morphological features of the samples were investigated by scanning electron microscopy (SEM), which showed that the morphologies of PbS and CdS were novel hierarchical dendrites, but rough exterior microspheres of ZnS, CoS and Cu2S. A possible reaction process was simply discussed in the end.
- Li, Kangfeng,Wang, Qiaojian,Cheng, Xianyi,Lv, Tianxi,Ying, Taokai
-
-
Read Online
- Thermal stability and kinetic studies of new dinuclear copper(II) complexes with octaazamacrocyclic and multidonor bidentate ligands
-
The thermal properties of four copper(II) complexes with N,N′,N″,N?-tetrakis(2-pyridylmethyl)-1,4,8, 11-tetraazacyclote-tradecane (tpmc) and several bidentate ligands N,S (thiosemicarbazide and thiourea) or N,O donors (semicarbazide and urea), of the general formula [Cu2(X)tpmc](ClO4)4, have been investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). The thermal stability order can be recognized for the examined complexes, depending on coordinated bidentate bridging N,S or N,O ligand. Kinetic data demonstrated first-order thermal decomposition. A plausible mechanism has been proposed which explains the major products of the degradation.
- Sovilj, Sofija P.,Babi?-Samard?ija, Ksenija,Mini?, Dragica M.
-
-
Read Online
- Refined Crystal Structures of SrLnCuS3 (Ln = Er, Yb)
-
According to powder X-ray diffraction data, the crystal structures of compounds SrLnCuS3 (Ln = Er, Yb) have been refined by minimizing the derivative difference in the anisotropic approximation for all atoms. Crystals are orthorhombic, space group Cmcm, structure type KZrCuS3: a = 3.93128(3) ?, b = 12.9709(1) ?, c = 10.1161(1) ?, V = 515.843(9) ?3, ρcalc = 5.337 g/cm3, Z = 4, RDDM = 3.73%, RF = 2.06% (SrErCuS3); a = 3.91448(4) ?, b = 12.9554(1) ?, c = 10.0332(1) ?, V = 508.842(8) ?3, ρcalc = 5.487 g/cm3, Z = 4, RDDM = 3.56%, RF = 1.48% (SrYbCuS3). The structure of SrLnCuS3 is described by [LnCuS3] twodimensional layers formed by distorted CuS4 tetrahedra and LnS6 octahedra with Sr2+ ions residing between the layers. The compounds are transparent for IR radiation in the range 3200–1800 cm–1.
- Ruseikina,Solov’ev,Galenko,Grigor’ev
-
-
Read Online
- Syntheses, structures, physical properties, and theoretical studies of CeMxOS (M = Cu, Ag; x ≈ 0.8) and CeAgOS
-
Black single crystals of the two nonstoichiometric cerium coinage-metal oxysulfide compounds CeCuxOS and CeAgxOS (x ≈ 0.8) have been prepared by the reactions of Ce2S3 and CuO or Ag2O at 1223 or 1173 K, respectively. A black powder sample of CeAgOS has been prepared by the stoichiometric reaction of Ce2S 3, CeO2, Ag2S, and Ag at 1073 K. These isostructural materials crystallize in the ZrSiCuAs structure type with two formula units in the tetragonal space group P4/nmm. Refined crystal structure results and chemical analyses provide evidence that the previously known anomalously small unit-cell volume of LnCuOS for Ln = Ce (Ln = rare-earth metal) is the result of Cu vacancies and the concomitant presence of both Ce 3+ and Ce4+. Both CeCu0.8OS and CeAgOS are paramagnetic with μeff values of 2.13(6) and 2.10(1) μB, respectively. CeCu0.8OS is a p-type semiconductor with a thermal activation energy Ea = 0.22 eV, σ electrical = 9.8(1) 10-3 S/cm at 298 K, and an optical band gap E9 conductivity = 0.16(4) S/cm and an optical band gap E 9 = 0.71 eV at 298 K. Theoretical calculations with an on-site Coulomb repulsion parameter indicate that the Ce 4f states are fully spin-polarized and are not localized in CeCuOS, CeCu0.75OS, or CeAgOS. Calculated band gaps for CeCu0.75OS and CeAgOS are 0.6 and 0.8 eV, respectively.
- Chan, George H.,Deng, Bin,Bertoni, Mariana,Ireland, John R.,Hersam, Mark C.,Mason, Thomas O.,Van Duyne, Richard P.,Ibers, James A.
-
-
Read Online
- Compounds with layered structures in the systems CuGa5S8/CuIn5S8 and AgGa5S8/AgIn5S8
-
The title systems have been investigated by single crystal and powder X-ray diffraction methods on quenched samples. In the system AgGaxIn5-xS8 spinel type phases are formed up to x A compound crystallising with a hexagonal layered structure is obtained for 2 a single crystal of composition AgGa3In2S8: space group P63mc, Z = 2, a = 380.80 and c = 3076.4 pm. The structure is isotypic to the Zn2In2S5 (II a) type. The sample AgGa4InS8 crystallises in a Wurtzite like structure with a = 377.25 and c = 616.1 pm. In the system CuGaxIn5-xS8 a new compound with layered structure has been detected for 1 ≤ x ≤ 2 which crystallises hexagonally with a = 380.28 and c = 3073.4 pm (x = 2). For the spinel CuIn5S8 an exchange of In by Ga is not detected. Wiley-VCH Verlag GmbH, 2001.
- Haeuseler,Elitok,Memo,Arzani
-
-
Read Online
- One-step synthesis of Cu2S nanostructures with two different morphologies on either side of a copper substrate
-
Cu2S nanosheets and hexagonal nanoplates have been synthesized, respectively on either side of a copper substrate via a facile one-step hydrothermal process using ethylenediamine (en) and distilled water as co-solvent and cetyltrimethylammonium
- Lv, Sa,Suo, Hui,Zhao, Xu,Wang, Chunxu,Zhou, Tieli,Jing, Shengyu,Xu, Yanan,Zhao, Chun
-
-
Read Online
- Controllable synthesis of Cu-based nanocrystals in ODA solvent
-
We exploited a solution-based route for preparation of Cu, Cu2O, Cu3N, and Cu2S nanocrystals, that is, direct thermal decomposition of copper salts (Cu(NO3)2, CuSO4) in octadecylamine (ODA) solvent, which is a novel and ingenious chemical process.
- Wang, Dingsheng,Li, Yadong
-
-
Read Online
- Phase equilibria in the Cu-Cu2S-as system
-
Phase equilibria in the Cu-Cu2S-Assystem have been studied by DTA and X-ray powder diffrac- tion. Cu0.667S0.333-As, Cu0.667S0.333-Cu0.735As0.265, and Cu0.8S0.2/s
- Gasanova,Aliev,Yusibov,Babanly
-
-
Read Online
- Achievement of extra-high thermoelectric performance in doped copper (I) sulfide
-
The development of nontoxic and inexpensive thermoelectric copper (I) sulfide (Cu2S)-based materials could enable an increase in the application of thermoelectric materials in the domain of energy conversion. By using melt quenching, mechanical alloying and spark plasma sintering, we successfully prepared doped and undoped Cu2S with excellent thermoelectric properties. Owing to the increase of carrier concentration, the electrical conductivity of the dopants enhanced from 2.0 × 104 S/m to 1.0 × 105 S/m, with the highest value acquired for Mn doped Cu2S of about 1.0 × 105 S/m at 350 K. Besides, Cu1.8Sn0.1Mn0.1S, Cu1.9Mn0.1S, and Cu1.9Sn0.1S followed an increasing variation in Seebeck coefficient with final values of 325 μV K?1, 322 μV K?1, and 294 μV K?1 at 800 K, respectively. The maximum power factor of 3.24 mW m?1 K?2 is obtained for Cu1.9Mn0.1S at 650 K, which is about 40 times greater than undoped Cu2S (0.08 mW m?1 K?2). At the same time, a peak ZT of 1.63 is attained at 700 K for Cu1.9Mn0.1S, which is about 18 times enhanced over undoped Cu2S (0.09).
- Li, Guihui,Lou, Shiyun,Nkemeni, Darrin Sime,Yang, Zhe,Zhou, Shaomin
-
-
Read Online
- The First Thiostannate Compound with Copper(II) Synthesized Under Ambient Conditions: Crystal Structure, Electronic and Thermal Properties
-
The new compound {[Cu(cyclam)]2[Sn2S6]}n·2nH2O containing Cu(II) was synthesized at room temperature reacting aqueous solutions of Na4SnS4·14H2O and of [Cu(cyclam)](ClO4)2. A crystalline precipitate consisting of small crystallites was formed after a very short reaction time of 2 h. Structure analysis reveals that [Sn2S6]4– anions are joined by the [Cu(cyclam)]2+ cations via Cu–S bonds generating layers which are stacked along the crystallographic a-axis. The Cu(II) centers are in a distorted octahedral environment of four N and two S atoms. The distortion is reflected in the EPR spectrum that displays the A∥ lines characteristic for Cu2+ (I = 3/2) and due to g∥ > g⊥ > 2.0023, the unpaired electron is located in the dx2–y2 orbital. The crystal water molecules can be removed at elevated temperatures, while crystallinity of the sample is mainly retained. Storage of the dehydrated sample on air leads to water uptake and recovery of the pristine compound.
- Benkada, Assma,Reinsch, Helge,Bensch, Wolfgang
-
-
Read Online
- Mobile copper ions as heat carriers in polymorphous copper sulfide superionic conductors
-
Liquid-like mobile Cu+ ions are generally considered as phonon scatters in copper chalcogenide superionic conductors, but this is recently disproved by a neutron spectroscopy study on lattice dynamics of Cu2Se compound [Voneshen et al., Phys. Rev. Lett. 17, 118 (2017)]. In this work, we provide a different perspective by investigating the thermal transport of three transformable polymorphs of Cu2S compounds with varying Cu+ content. We show that the disordered and mobile Cu+ ions are not the primary factor for suppressing the heat transport. A notable dependence of thermal conductivity on Cu+ content is observed. By correlating the electrically deducted thermal conductivity with the ion motion behavior for β-Cu2S superionic phase, we reveal that these fast ionic species Cu+ are heat carriers instead, which make an appreciable contribution to thermal conduction.
- Liang, Xin
-
-
Read Online
- A generally synthetic route to semiconducting metal sulfide nanocrystals by using corresponding metal powder and cysteine as metallic and sulfuric sources, respectively
-
The economical and large-scale preparations of metallic sulfides nanocrystals (NCs) would determine their practical industrial application. In this contribution, a series of sulfides NCs such as ZnS, CdS, PbS, Cu xS, MnS and Bi2S3, have been harvested by thermolysis of a single source metal cysteinate obtained conveniently from the reaction between metal powder and cysteine in aqueous environment and constant atmosphere in glassware. The characterizations including TEM, XRD, UV-Vis, FT-IR, TG-DSC, EDX and BET confirmed that the as-synthesized products are from the decomposition of metal cysteinate, of nanoscale in size, and of mesoporous materials. The generation, low cost and benign environment made this route technologically and scientifically interesting for the preparation of metallic sulfides NCs.
- Yu, Leshu,Lv, Yingying,Chen, Guangda,Zhang, Xiaolan,Zeng, Yawen,Huang, Heyong,Feng, Yuying
-
-
Read Online
- The phase diagrams of M2X-SiX2 (M is Cu, Ag; X is S, Se)
-
The phase diagrams of Cu2S-SiS2, Ag2S-SiS2 and Ag2Se-SiSe2 were investigated by DTA and X-ray methods. The system Cu2S-SiS2 contains two compounds: Cu2SiS3 and Cu8SiS6. The compound Cu6Si2S7 does not exist. The phasediagram of Ag2S-SiS2 is characterized by the presence of two ternary co mpounds: Ag8SiS6 and Ag10Si3S11. The Ag2Se-SiSe2 system contains only Ag8SiSe6, which forms a eutectic on either side. The stability range and the X-ray diffraction data of the compounds are presented.
- Venkatraman, Mahadevan,Blachnik, Roger,Schlieper, Andreas
-
-
Read Online
- Interfacial Engineering of CuCo2S4/g-C3N4Hybrid Nanorods for Efficient Oxygen Evolution Reaction
-
Altering the morphology of electrochemically active nanostructured materials could fundamentally influence their subsequent catalytic as well as oxygen evolution reaction (OER) performance. Enhanced OER activity for mixed-metal spinel-type sulfide (CuCo2S4) nanorods is generally done by blending the material that has high conductive supports together with those having a high surface volume ratio, for example, graphitic carbon nitrides (g-C3N4). Here, we report a noble-metal-free CuCo2S4 nanorod-based electrocatalyst appropriate for basic OER and neutral media, through a simple one-step thermal decomposition approach from its molecular precursors pyrrolidine dithiocarbamate-copper(II), Cu[PDTC]2, and pyrrolidine dithiocarbamate-cobalt(II), Co[PDTC]2 complexes. Transmission electron microscopy (TEM) images as well as X-ray diffraction (XRD) patterns suggest that as-synthesized CuCo2S4 nanorods are highly crystalline in nature and are connected on the g-C3N4 support. Attenuated total reflectance-Fourier-transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy studies affirm the successful formation of bonds that bridge (Co-N/S-C) at the interface of CuCo2S4 nanorods and g-C3N4. The kinetics of the reaction are expedited, as these bridging bonds function as an electron transport chain, empowering OER electrocatalytically under a low overpotential (242 mV) of a current density at 10 mA cm-2 under basic conditions, resulting in very high durability. Moreover, CuCo2S4/g-C3N4 composite nanorods exhibit a high catalytic activity of OER under a neutral medium at an overpotential of 406 mV and a current density of 10 mA cm-2.
- Biswas, Rathindranath,Thakur, Pooja,Kaur, Gagandeep,Som, Shubham,Saha, Monochura,Jhajhria, Vandna,Singh, Harjinder,Ahmed, Imtiaz,Banerjee, Biplab,Chopra, Deepak,Sen, Tapasi,Haldar, Krishna Kanta
-
-
Read Online
- Formation of CuS submicrotubes with quadrate cross section
-
CuS submicrotubes with quadrate cross section were synthesized by two simple steps: (i) preparation of copper-thiourea (Tu) complex; and (ii) subsequent reaction of the as-prepared complex with Na2S solution. Copper-Tu complex was characterized
- Yan,Huang,Jia,Luo
-
-
Read Online
- Thermal decomposition kinetics of M (mnt) (5-NO2-phen) (M=CoII, CuII, ZnII) complexes
-
Studies of the non-isothermal decomposition of M (mnt) (5-NO2-phen) (M=CoII, CuII, ZnII) were carried out by thermogravimetry. The thermal decomposition mechanisms and associated kinetics have been investigated.
- Donghua, Chen,Yuhong, Yuan,Zhenghe, Peng,Lihua, Jian,Qingcai, Pan,Zibin, Qin
-
-
Read Online
- Fabrication and SERS properties of Ag/Cu2S composite micro-nanostructures over Cu foil
-
A new kind of Ag/Cu2S composite micro/nanostructures has been prepared via a convenient galvanic reduction method. SEM images of these micro/nanostructures showed that Ag nanoparticles with the size of around 50-100 nm were well deposited on the surface of Cu2S micro/nanostructures. The SEM images also indicated that the Ag nanoparticles were preferentially grown on the big polygonal Cu2S microstructures, which could be explained by a localization of the electrons on the surface of the polygonal Cu2S microstructures after the electron transfer step. Owing to the introduction of Ag nanoparticles on the surface of Cu2S micro/nanostructures, the resulting Ag/Cu2S composite micro-nanostructures could be used as a versatile substrate for surface enhanced Raman scattering.
- Song, Wei,Wang, Jinjie,Mao, Zhu,Xu, Weiqing,Zhao, Bing
-
-
Read Online
- Tuning of p-n-p-Type Conduction in AgCuS through Cation Vacancy: Thermopower and Positron Annihilation Spectroscopy Investigations
-
Understanding the complex phenomenon behind the structural transformations is a key requisite to developing important solid-state materials with better efficacy such as transistors, resistive switches, thermoelectrics, etc. AgCuS, a superionic semiconductor, exhibits temperature-dependent p-n-p-type conduction switching and a colossal jump in thermopower during an orthorhombic to hexagonal superionic transition. Tuning of p-n-p-type conduction switching in superionic compounds is fundamentally important to realize the correlation between electronic/phonon dispersion modulation with changes in the crystal structure and bonding, which might contribute to the design of better thermoelectric materials. Herein, we have created extrinsic Ag/Cu nonstoichiometry in AgCuS, which resulted in the vanishing of p-n-p-type conduction switching and improved its thermoelectric properties. We have performed the selective removal of cations and measured their temperature-dependent thermopower and Hall coefficient, which demonstrates only p-type conduction in the Ag1-xCuS and AgCu1-xS samples. The removal of Cu is much more efficient in arresting conduction switching, whereas in the case of Ag vacancy, p-n-p-type conduction switching vanishes at higher vacant concentrations. Positron annihilation spectroscopy measurements have been done to shed further light on the mechanisms behind this structural transition-dependent conduction switching. Cation (Ag+/Cu+) nonstoichiometry in AgCuS significantly increases the vacancy concentration, hence, the p-type carriers, which is confirmed by positron annihilation spectroscopy and Hall measurement. The Ag1-xCuS and AgCu1-xS samples exhibit ultralow thermal conductivity (～0.3-0.5 W/m·K) in the 290-623 K temperature range because of the low-energy cationic sublattice vibration that arises as a result of the movement of loosely bound Ag/Cu within the stiff S sublattice.
- Dutta, Moinak,Sanyal, Dirtha,Biswas, Kanishka
-
-
Read Online
- The phase equilibria in the quasi-ternary Cu2S-CdS-SnS2 system
-
The phase equilibria in the quasi-ternary system Cu2S-CdS-SnS2 has been investigated using differential thermal, X-ray phase, microstructural and energy-dispersive X-ray analyses. The projection of the liquid surface and the isotherm
- Piskach,Parasyuk,Olekseyuk
-
-
Read Online
- One-pot synthesis of 3D Cu2S-MoS2 nanocomposites by an ionic liquid-assisted strategy with high photocatalytic activity
-
Novel 3D Cu2S-MoS2(x?:?y) nanocomposites with different proportions of Cu2S (x) and MoS2 (y) are synthesized successfully by a one-step hydrothermal method with the assistance of the ionic liquid [BMIM]SCN. The characterization results show that the nanocomposites are self-assembled from nanosheets of Cu2S and MoS2, they display nanoflower morphology and a typical mesoporous structure. The fabrication mechanism of the nanocomposites is investigated using time-dependent experiments, which indicate the key role of the ionic liquid (IL) in the synthesis process. Furthermore, TAA is used as a sulfur source instead of the IL to form a Cu2S-MoS2 nanocomposite, with the aim of further investigating the effects of the IL on the morphology of the composite. Photodegradation of MB under visible light irradiation experiments were used as probe reactions to evaluate the photocatalytic performance of the as-prepared samples. All the nanocomposites show better catalytic activity than Cu2S and MoS2 monomers. Among the different Cu2S-MoS2(x?:?y) nanocomposites, the Cu2S-MoS2(1?:?1) composite exhibits the most excellent photocatalytic performance and cycling stability.
- Chen, Ya,Su, Penghe,Liu, Xiaotong,Liu, Hongchi,Zhu, Baolin,Zhang, Shoumin,Huang, Weiping
-
-
Read Online
- Effect of potassium hydrogen phthalate (C8H5KO4) on the one-step electrodeposition of single-phase CuInS2 thin films from acidic solution
-
The effect of potassium hydrogen phthalate (C8H5KO4) as a special additive on the one-step electrodeposition of single-phase CuInS2 thin films from acidic solution (pH 2.5) was investigated in detail. The XRD, SEM and UV-vis-NIR characterization confirms that the addition of an adequate concentration of C8H5KO4 (23 mM) to the electrolytic bath containing 12.5 mM Cu2+, 10 mM In3+, 40 mM S2O32- and 100 mM LiCl can contribute greatly to the controllable growth of pure chalcopyrite CuInS2 films with uniform surfaces and an ideal band gap of approximately 1.54 eV. Complexation studies of C8H5KO4 with Cu2+ and In3+ in electrolytic solutions indicated that C8H5KO4 can complex Cu2+ more strongly than In3+ and move the electrode potentials of Cu2+ and In3+ near each other as determined by polarization analysis. Furthermore, the potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) analysis performed in a series of solution systems revealed a three-step reaction mechanism for CuInS2 deposition and considerable adsorption of C8H5O4- and Cu(C8H5O4)+ to the cathode surface. This deposition shows that the synergetic effects of complexation and adsorption originated from the additive on the Cu2+ electro-reduction, thus promoting the co-deposition of copper, indium and sulfur in the form of single-phase CuInS2.
- Xu, Xinhua,Wang, Feng,Liu, Jingjun,Ji, Jing
-
-
Read Online
- Synthesis, crystal structure, and properties of novel perovskite oxychalcogenides, Ca2CuFeO3Ch (Ch = S, Se)
-
Two new perovskite oxychalcogenides, Ca2CuFeO3S and Ca2CuFeO3Se, have been synthesized in evacuated quartz tubes. They crystallize in P4/nmm space group with lattice parameters a = 3.8271(1), c = 14.9485(2) and a = 3.8605(1), c = 15.3030(2) for Ca 2CuFeO3S and Ca2CuFeO3Se, respectively. They appear to be the first layered chalcogenide perovskites involving calcium and are structural analogs of the corresponding Sr and Ba compounds. The new compounds exhibit semiconducting properties with energy gap decreasing from the oxysulfide to the oxyselenide. Possibility of introducing Ca2+ into structures of known layered oxychalcogenides and oxypnictides is discussed.
- Charkin,Sadakov,Omel'Yanovskii,Kazakov
-
-
Read Online
- Reactivity in the system copper-arsenic-sulfur I. The formation of Cu3AsS4, enargite
-
The reaction pathways in the synthesis of Cu3AsS4 have been studied in the DTA in the range 25-870°C with a heating rate of 10 K/min. Educts, intermediates and products were characterised by X-ray diffraction. Educts were the elements and the binary compounds Cu3-xAs, Cu5-δAs2, As4S4, As2S3, the two copper(I) sulfides Cu1.91S, Cu2S and CuS. The 19 examined educt mixtures are divided by their thermal effects during reaction into three groups. Mixtures of the group I have low copper or copper arsenide contents. Educts in group II are mainly copper arsenides and sulfur, and educts of group III enclose all other mixtures, including that from the elements. In all cases the reaction to Cu3AsS4 proceeds stepwise. The various intermediates are mainly the binary compounds CuS and As4S4 at lower temperatures and at higher temperatures the ternary compounds Cu6As4S9, Cu4As2S5 or Cul2+xAs4+ySl3. The synthesis is complete at approximately 600°C. Heating above the melting point of Cu3AsS4 at 694°C increases the amount of by-products. In grinding and ageing experiments copper arsenides react with sulfur, As2S3, and CuS to metastable Cu2As. The reaction between Cu3-xAs + S does not proceed by treatment in a planetary ball mill. As4S4 + CuS do not react during mediumised milling, but the formation of Cu3AsS4 occurs after this treatment in one step in the DTA run. The desoxidation of copper powders is a decisive influence factor for the reaction from the elements.
- Müller,Blachnik
-
-
Read Online
- Ultrahigh Thermoelectric Performance in Mosaic Crystals
-
Successful research strategies to enhance the dimensionless figure of merit zT above 2 rely on either bulk nanomaterials or on single crystals. A new physical mechanism of nanoscale mosaicity is shown that goes beyond the approaches in single crystals or conventional nanomaterials. A zT value of 2.1 at 1000 K in bulk nanomaterials is achieved.
- He, Ying,Lu, Ping,Shi, Xun,Xu, Fangfang,Zhang, Tiansong,Snyder, Gerald Jeffrey,Uher, Ctirad,Chen, Lidong
-
-
Read Online
- Hall effect and surface characterization of Cu2S and CuS films deposited by RF reactive sputtering
-
CuxS is one of the most prevalent minor phases co-existing in CuInS2 films. In order to understand its influence on CuInS2, we first focus our study on the binary compound CuxS. Cu2S, and CuS films were deposited on float glass substrates using a reactive RF sputter process with optimized sputter parameters, such as power, temperature of the substrate, and the gas flow of the H2S. X-ray diffraction spectra showed that the Cu2S films have (002) preferential orientation, and both compounds have a hexagonal structure. The surface morphology and the composition of the layers were analyzed by atomic force microscopy and Rutherford back-scattering spectroscopy, respectively. X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy were used to characterize the layer surfaces, as well as the surface composition. Hall-effect measurements were carried out to determine the electrical properties of the films.
- He,Polity,?sterreicher,Pfisterer,Gregor,Meyer,Hardt
-
-
Read Online
- Photoelectrochemistry of pure and core/sheath nanowire arrays of Cu 2S directly grown on copper electrodes
-
Photoelectrochemistry (PEC) of straight and isolated Cu2S nanowires arrayed on a copper foil is studied. A cathodic photocurrent is observed, which increases with the increasing negative bias of the film electrode, conforming to the p-type semiconducting nature of Cu2S. PEC studies on the core/sheath nanowires of Cu2S (Cu2S nanowires coaled with other nanoparticles such as CdS, polypyrrole, and Au) have revealed distinctly different characteristics. Cu2S/CdS nanowires exhibit a slightly higher photocurrent response due to the charge transfer between the p-type Cu2S core and n-type CdS sheath, whereas the photocurrent response obtained for Cu2S/PPy nanowires is generally an order of magnitude smaller than that for pure Cu2S nanowires under the same bias voltage. For Cu2S/Au nanowires, however. Au nanoparticles can readily accept the photogenerated electrons from the conduction band of Cu2S; this redirects the electron transfer pathway and results in the anodic photocurrent response. On the basis of these findings, different photocurrent generation mechanisms are proposed.
- Tang, Shangfeng,Wen, Xiaogang,Zhang, Weixin,Yang, Shihe
-
-
Read Online
- Growth and characterization of CuxS (x=1.0, 1.76, and 2.0) thin films grown by solution growth technique (SGT)
-
Thin films of CuxS (x=1.0, 1.76, and 2.0) were grown by solution growth technique (SGT). The deposition parameters such as pH of solution, deposition time, and deposition temperature were optimized. The deposited films were annealed in Ar atmosphere at 250 °C. The changes in structural and optical transport phenomenon of annealed films have been studied. The surface morphology and composition of films were studied by SEM micrographs and EDAX analysis, respectively, and the surface roughness was calculated by atomic force microscopy (AFM). The XRD study showed the polycrystalline nature of annealed film. The lattice parameters of different phases of the material were calculated from the XRD pattern. The absorption coefficient varies in the range of 1×105-6×105 cm-1. The optical bandgaps of CuS, Cu1.76S, and Cu2S are 1.72, 2.11, and 2.48 eV, respectively.
- Bagul,Chavhan,Sharma, Ramphal
-
-
Read Online
- ELECTROCRYSTALLIZATION OF COPPER SULPHIDE (CU2S) ON COPPER.
-
The anodic formation of copper sulfide on copper was studied at various pH and sulfide concentrations. The kinetics and mechanism of film formation were elucidated by cyclic voltammetry and transient techniques. It was found that the film grows by a nucleation and growth mechanism controlled by localized hemispherical diffusion which, at long times, turns into linear diffusion due to overlapping of the diffusion zones of neighbouring centers. The analysis indicates that the number of active centers available for the nuclei formation is finite. The kinetic parameters for the nucleation have been interpreted according to the classical and atomistic models of nucleation. It is also shown that potentiostatic and galvanostatic techniques give comparable results.
- Scharifker,Rugeles,Mozota
-
-
Read Online
- Mixed-metal thiophosphate CuCd3PS6: An infrared nonlinear optical material activated by its three-in-one tetrahedra-stacking architecture
-
Novel mixed-metal thiophosphate CuCd3PS6 has been firstly discovered and fully characterized. Careful experimental and theoretical investigations demonstrate that CuCd3PS6 is a benign infrared nonlinear optical material with a moderate second harmonic generation response of 0.9 × AgGaS2 at 41-74 μm, a large laser damage threshold of 4.1 × AgGaS2, a wide band gap of 2.24 eV and a low melting point of 603 °C. Moreover, first principles calculations indicate that CuCd3PS6's intriguing nonlinear optical performance is activated by its three-in-one tetrahedra-stacking architecture.
- Guo, Yangwu,Li, Chunxiao,Li, Zhuang,Lin, Zheshuai,Wu, Yicheng,Xing, Wenhao,Yao, Jiyong,Zhang, Shengzi
-
supporting information
p. 5020 - 5024
(2020/04/28)
-
- Facile photocatalytic reduction of carcinogenic Cr(vi) on Fe-doped copper sulfide nanostructures
-
In this study, Fe-doped copper sulfide nanoparticles (NPs) were investigated for the solar-assisted reduction of CrVI ions in raw water. The Fe-doped NPs were synthesized by decomposing copper(ii) N,N-diphenylmethylpiperazinecarbamodithioate via a facile single-step, one-pot solvothermal method in the presence of iron salt. The CrVI photoreduction data were fit to a pseudo-first-order kinetic model and a Langmuir model. The CuS/Cu2S NP reduction ability for CrVI increases with an increase in dopant percentage. The best catalyst (9% Fe-doped) was able to reduce CrVI (10-4 M K2Cr2O7) to CrIII in raw water using an initial amount of 10 mg in 6 min with a reduction efficiency of up to 100%. The photocatalytic activity was examined while varying five different parameters: sunlight, diffused light, change in pH, and changes in the concentration of the catalyst and the temperature. This new approach presents an active, simple, and cost-effective means for wastewater treatment.
- Aamir, Asma,Ain, Noor Ul,Nasir, Jamal Abdul,Nayab, Ujala,Rehman, Zia Ur
-
p. 27377 - 27386
(2020/08/17)
-
- Optimal d-band-induced Cu3N as a cocatalyst on metal sulfides for boosting photocatalytic hydrogen evolution
-
The development of highly active and non-noble cocatalysts is crucial for sustainable hydrogen (H2) generation through photocatalytic water splitting. Herein, Cu3N nanocrystals (～15 nm) have been first used as a cocatalyst coupled with CdS for efficient photocatalytic H2 evolution with a rate of ～4512 μmol g-1 h-1, achieving a dramatic improvement of 851-fold compared to bare CdS. Mechanistic studies revealed that the appropriate d-band center of Cu3N (-1.875 eV) with promoted photogenerated charge carrier kinetics induced its intrinsic activity, as a result of the balance between the adsorption and desorption of H species.
- Guo, Qing,Huang, Limin,Li, Xu-Bing,Liang, Fei,Sun, Zongzhao,Wang, Yang,Wu, Li-Zhu,Xia, Shu-Guang,Zhang, Z. Conrad
-
supporting information
p. 22601 - 22606
(2020/11/21)
-
- Phase Equilibria in Systems DyCuS2–EuS and Cu2S?Dy2S3?EuS
-
The phase diagram of system DyCuS2–EuS has been first constructed, and the phase equilibria in the Cu2S–Dy2S3–EuS triangle at 970 K have been studied. Compound EuDyCuS3 (1DyCuS2 : 1EuS), space group Pnma, a = 10.1901(3) ?, b = 3.9270(1) ?, c = 12.8468(3) ?, melts incongruently at 1727 ± 7 K according to the reaction: EuDyCuS3solid ? 0.17 SS EuS (90 mol % EuS, 10 mol % DyCuS2) + 0.83 liq (42 mol % EuS, 58 mol % DyCuS2), ΔH = 2.9 ± 0.6 kJ/mol; microhardness of the phase is 3080 ± 35 MPa. Compound EuDyCuS3 is transparent in the range 3000–1800 cm–1. In system DyCuS2–EuS, the solid solution (SS) based on EuS extends from 91 to 100 mol % at 1770 K and from 92 to 100 mol % at 1170 K. In γ-DyCuS2, 2 mol % EuS dissolves at 1487 K. The eutectic is formed between compounds DyCuS2 and EuDyCuS3 at 12 mol % EuS, T = 1487 ± 8 K. In system Cu2S?Dy2S3?EuS, 10 secondary systems have been isolated. At 970 K, tie-lines are located between compound EuDyCuS3 and solid solutions based on compounds β-Cu2S, EuS, DyCuS2, β-(DyCu3S3), and EuDy2S4; between DyCuS2 and the solid solution of α-Dy2S3, DyCuS2, and EuDy2S4.
- Ruseikina,Andreev
-
p. 1494 - 1500
(2018/11/25)
-
- Phase equilibria in the Cu2S–Cu3AsS4–S system
-
Phase equilibria in the Cu2S–Cu3AsS4–S system were studied by differential thermal analysis and X-ray powder diffraction. Important plots characterizing this system were constructed, namely, the T–x diagrams of the lateral quasi-binary systems Cu2S–Cu3AsS4 and Cu3AsS4–S, some internal sections, the isothermal section of the phase diagram at 300 K, and the projection of the liquidus surface. The fields of primary crystallization of phases and the types and coordinates of in- and monovariant equilibria were found. A wide region of separation of liquid phases was detected in the system.
- Gasanova,Mashadieva,Yusibov, Yu. A.,Babanly
-
p. 591 - 597
(2017/06/09)
-
- High performance stoichiometric Cu2S cathode on carbon fiber current collector for lithium batteries
-
In this study, stoichiometric Cu2S with monoclinic crystal structure with space group P21/c was prepared via spray pyrolysis with followed heat treatment. Its electrochemical properties were investigated after coating on a carbon fib
- Kalimuldina, Gulnur,Taniguchi, Izumi
-
p. 329 - 336
(2016/12/23)
-
- Synthesis of Nonstoichiometric Cu2ZnSnS4 from ZnS by Cation Exchange
-
A cation exchange reaction of wide-band-gap crystalline ZnS with CuCl2 and SnCl4 in triethylene glycol was developed to synthesize nonstoichiometric Cu2ZnSnS4 with crystallite size more than 100 nm. The materials were characterized by powder X-ray diffraction, electron microscopy, Raman, and energy dispersive X-ray elemental mapping. The method allows the formation of Zn-rich phases and good control of the crystal size and shape. No narrow-band-gap highly conductive CuxS impurities were observed.
- Jin, Yi,Chumanov, George
-
supporting information
p. 3761 - 3766
(2017/08/30)
-
- Preparation of Sn-doped CuAlS2 films with an intermediate band and wide-spectrum solar response
-
As a member of Cu-containing chalcopyrites, CuAlS2 is a promising candidate material for intermediate band solar cells (IBSCs). In this paper, the intermediate band mechanism of Sn doped CuAlS2 was investigated both theoretically and experimentally, and the two sub-bandgaps were measured to be 1.91 eV and 1.31 eV, respectively. A novel and convenient method of Electrophoretic Deposition (EPD) was utilized to prepare Sn doped CuAlS2 films. Due to the wide-spectrum of absorption introduced by the intermediate band, Sn doped CuAlS2 films showed better photoelectrochemical performance (PEC).
- Guo, Chenguang,Yang, Chongyin,Xie, Yian,Chen, Ping,Qin, Mingsheng,Huang, Rongtie,Huang, Fuqiang
-
p. 40806 - 40810
(2016/05/24)
-
- Synthesis of CZTS nanoparticles for low-cost solar cells
-
In this work, uniformly sized Cu2ZnSnS4 (CZTS) nanoparticles with easy control of chemical composition were synthesized and printable ink containing CZTS nanoparticles was prepared for low-cost solar cell applications. In addition, we studied the effects of synthesis conditions, such as reaction temperature and time, on properties of the CZTS nanoparticles. For CZTS nanoparticles synthesis process, the reactants were mixed as the 2:1:1:4 molar ratios. The reaction temperature and time was varied from 220°C to 320°C and from 3 hours to 5 hours, respectively. The crystal structure and morphology of CZTS nanoparticles prepared under the various conditions were investigated by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDS) was used for compositional analysis of the CZTS nanoparticles.
- Kim, Donguk,Kim, Minha,Shim, Joongpyo,Kim, Doyoung,Choi, Wonseok,Park, Yong Seob,Choi, Youngkwan,Lee, Jaehyeong
-
p. 5082 - 5086
(2016/06/09)
-
- Effects of surfactant and reaction time on the formation and photocatalytic performance of Cu2S thin films grown in situ on Cu foil by hydrothermal method
-
Cu2S thin films were successfully grown in situ on Cu foil by an easy hydrothermal method. The effects of surfactant and reaction time on the formation of the Cu2S films were studied by X-ray diffraction, field-emission scanning electron microscopy and ABIOS profilometry. Results showed that the thin films consisted of nanoparticles, and their crystallization and surface roughness depended on the structures of surfactants and reaction time. Photocatalytic studies indicated that the film obtained at 1 h by the EDTA-2Na surfactant exhibited a good methylene blue degradation rate of 83.7%, and higher values of 89.2% and 90% were obtained with increased reaction time to 3 and 4 h. Even the decomposition rate remained at high (82%) after reuse. This good catalytic performance can be attributed to the heterojunction formed between Cu and Cu2S, the special surface from the reaction between [Cu-EDTA]- ion and S2-, and the further crystal orientation with prolonged reaction time.
- Liu, Jinsong,Wu, Zhengying,Zhu, Kongjun,Li, Ziquan,Feng, Bing,Gu, Qilin,Liu, Pengcheng,Zhang, Shuo,You, Yuncheng,Wang, Bijun,Wang, Jing,Qiu, Jinhao
-
p. 266 - 271
(2016/06/13)
-
- Copper(i) 5-phenylpyrimidine-2-thiolate complexes showing unique optical properties and high visible light-directed catalytic performance
-
Solvothermal reactions of 5-phenylpyrimidine-2-thiol (5-phpymtH) with equimolar CuBr afforded one hexanuclear cluster [Cu6(μ3-5-phpymt)6] (1) along with a tetranuclear by-product [{(Cu2Br)(μ-5-phpymtH)}(μ3-5-phpymt)]2 (2). A two dimensional (2D) polymer [Cu4(μ5-5-phpymt)2(μ-Br)2]n (3) was isolated from the reaction of 5-phpymtH with two equiv. of CuBr. Analogous reactions of 5-phpymtH with one or four equiv. of CuI produced one tetranuclear cluster [{Cu2(μ-5-phpymtH)(μ-5-phpymt)}(μ3-I)]2 (4) and one 2D polymer [Cu6I2(μ4-I)2(μ4-5-phpymt)2]n (5). Compound 1 possesses a water-wheel-shaped hexameric structure. Compound 2 has an H-shaped tetrameric structure. Compound 3 possesses a 2D network in which unique 1D [Cu8(μ-Br)2(μ5-5-phpymt)4]n chains are connected by μ-Br- ions. Compound 4 has another tetrameric structure in which two {Cu2(μ-5-phpymtH)2(μ-5-phpymt)} fragments are linked by a pair of μ3-I- ions. Compound 5 contains another 2D network in which hexanuclear {Cu6I2(μ4-I)2} units are linked by μ4-5-phpymt bridges. The 5-phpymt ligand shows four coordination modes: μ-κ1(S)-κ1(N) (4), μ3-κ2(S)-κ1(N) (1 and 2), μ4-κ1(N)-κ2(S)-κ1(N′) (5) and μ5-κ1(N)-κ3(S)-κ1(N′) (3). Complex 1 shows strong solvatochromic behaviour and displays reversible luminescence switching upon alternate addition of CF3COOH and Et3N into its CHCl3 solution. Complexes 1-5 exhibit a high photocatalytic activity towards the aerobic oxidative hydroxylation of arylboronic acids to phenols under visible light irradiation. Catalyst 5 can be reused in several cycles without any obvious decay of the catalytic efficiency. These results offer an interesting insight into how the CuX/5-phpymtH molar ratios and X- ions exert great impacts on the coordination modes of the 5-phpymt- ligand, the structures of the final complexes, and the luminescence and catalytic properties.
- Zhang, Meng-Juan,Li, Hong-Xi,Li, Hai-Yan,Lang, Jian-Ping
-
p. 17759 - 17769
(2016/11/17)
-
- Optical and thermal properties of the EuLnCuS3 (Ln = La, Pr, Sm, Gd) compounds
-
We have studied the IR transmission of the EuLnCuS3 (Ln = La, Pr, Sm, Gd) compounds in the spectral range 400 to 4000 cm-1 and their thermal expansion in the temperature range 300-1450 K. The compounds have high IR transmission in th
- Murashko, Yu. A.,Ruseikina,Kislitsyn,Andreev
-
p. 1213 - 1218
(2015/11/02)
-
- Structure-property relationship studies of copper(I) complexes of nanosized hypodentate ligands and evaluation of their antitumor and antimicrobial activities
-
We report the preparation of four nanosized isomers of N-benzoyl-N′-(hydroxyphenyl) thioureas by nanoprecipitation. Direct reactions with CuCl2·2H2O gave the corresponding complexes in good yields. The structures of the ligands and their copper complexes were characterized using different analytical and spectroscopic measurements. In all complexes, the data revealed non-electrolytic mononuclear three-coordinate copper(I) complexes, where the ligand is hypodentate to copper ion via thioamide sulfur. Thermal studies revealed high thermal stability of the complexes compared to their parent ligands and the mechanism of decomposition and the thermodynamic parameters were evaluated. The ligands and their complexes were screened against different pathogenic microorganisms, and subjected to in vitro antioxidant and cytotoxic activities against three human cell lines. Compared to other isomers, N-benzoyl-N′-(o-hydroxyphenyl) thiourea exhibited significant antimicrobial activity and had higher activity than the standard fungicides and bacteriocides. All copper complexes showed inhibitory potencies, however [Cu(H2L2)2Cl] exhibited remarkable inhibitory activities against the examined cancer cell lines as evident by the range of IC50 values (4.0-7.4 g/mL) and the percentage of cell viability. The results obtained can find medical applications as new therapeutic nanoparticle agents.
- Elhusseiny, Amel F.,Eldissouky, Ali,Al-Hamza, Ahmed M.,Hassan, Hammed H.A.M.
-
p. 241 - 260
(2015/10/19)
-
- High thermoelectric performance in non-toxic earth-abundant copper sulfide
-
A new type of high performance thermoelectric material Cu2-xS composed of non-toxic and earth-abundant elements Cu and S is reported. Cu 2-xS surprisingly has lower thermal conductivity and more strikingly reduced specific heat compared to the heavier Cu2Se, leading to an increased zT to 1.7.
- He, Ying,Day, Tristan,Zhang, Tiansong,Liu, Huili,Shi, Xun,Chen, Lidong,Snyder, G. Jeffrey
-
p. 3974 - 3978
(2014/06/24)
-
- EuNdCuS3: Crystal structure of the high-temperature polymorph and properties
-
The X-ray diffraction structure of the high-temperature polymorph of complex sulfide EuNdCuS3 is determined. The phase we prepared has an orthorhombic structure with the unit cell parameters a = 8.0648(3) ?, b = 4.0207(1) ?, c = 15.7924(3) ?, space group Pnma, Z = 4, Ba2MnS3 type structure. The sample is IR transparent in the range 1800-2800 cm-1. Thermal expansion coefficient is found to experience jumps, which are characteristic of phase transitions.
- Ruseikina,Solovyev,Andreev,Kislitsyn
-
p. 1109 - 1114
(2015/02/02)
-
- Structure and morphology evolution in mechanochemical processed CuInS 2 powder
-
CuInS2 powders were synthesized by mechanochemical process from copper, indium and sulfur powders. A self-propagating combustion occurred during the milling process. Phase structure, morphology evolution and component uniformity of Cu-In-S system have been studied by X-ray diffraction, scanning electron microscope and energy dispersive analysis, respectively. Optical property of ball milled CuInS2 has been detected by UV-Vis spectroscopy. The results show that there is no intermetallic phase was observed before the self-propagating combustion though morphology changed obviously during this stage. The detected composition of mixed powder converges toward the original proportion with increased milling as the particle sizes decreased. Homogeneous CuInS2 particles less than 5 μm are obtained after milling 120 min. The reason of mechanically induced self-propagating reaction occurs during milling in this system is also discussed. The UV-Vis absorption spectrum shows the milled CuInS2 has a broad absorption over the entire visible light and extending into the near-infrared region and its band gap is 1.52 eV.
- Wu, Su-Mei,Xue, Yu-Zhi,Zhou, Li-Mei,Liu, Xiang,Xu, Ding-Yong
-
-
- On ammonium-bis(dithiocarbamato)-copper(I)-monohydrate and Mono(dithiocarbamato)-copper(I)
-
The title compounds NH4[Cu(S2CNH2) 2]·H2O (A) and CuS2CNH2 (B) were prepared from aqueous alcoholic solutions by reaction of ammoniumdithiocarbamate with copper sulfate in presence of excess cyanide as reductive. (A) crystallizes in the orthorhombic space group C2221 (No. 20) with a = 8.9518(6), b = 9.6414(6) and c = 10.6176(8) A, Z = 4. (B) crystallizes in the orthorhombic space group P212 121 (No. 19) with a = 5.9533(4), b = 6.6276(4) and c = 9.4834(5) A, Z = 4. In the crystal structure of (A) copper has a tetrahedral surrounding of four monodentate dithiocarbamate ligands. These structural units form 2D nets stacked along [001]. Staggered chains consisting of H2O and NH4+ penetrate the crystal structure along [001] yielding additional coherence via hydrogen bonds. The crystal structure of (B) comprises a three-dimensional tetrahedral framework of CuS 4 units exclusively linked by vertices. The arrangement is reminiscent of a filled β-cristobalite structure with the dithiocarbamate ligands extending into the hollow spaces. Thermal decomposition precedes stepwise finally giving Cu2S in each case.
- Teske, Christoph L.
-
p. 2767 - 2773
(2014/01/06)
-
- Near-infrared absorbing Cu12Sb4S13 and Cu3SbS4 nanocrystals: Synthesis, characterization, and photoelectrochemistry
-
Herein, we present the novel synthesis of tetrahedrite copper antimony sulfide (CAS) nanocrystals (Cu12Sb4S13), which display strong absorptions in the visible and NIR. Through ligand tuning, the size of the Cu12Sb4S13 NCs may be increased from 6 to 18 nm. Phase purity is achieved through optimizing the ligand chemistry and maximizing the reactivity of the antimony precursor. We provide a detailed investigation of the optical and photoelectrical properties of both tetrahedrite (Cu12Sb4S13) and famatinite (Cu3SbS4) NCs. These NCs were found to have very high absorption coefficients reaching 105 cm-1 and band gaps of 1.7 and 1 eV for tetrahedrite and famatinite NCs, respectively. Ultraviolet photoelectron spectroscopy was employed to determine the band positions. In each case, the Fermi energies reside close to the valence band, indicative of a p-type semiconductor. Annealing of tetrahedrite CAS NC films in sulfur vapor at 350 C was found to result in pure famatinite NC films, opening the possibility to tune the crystal structure within thin films of these NCs. Photoelectrochemistry of hydrazine free unannealed films displays a strong p-type photoresponse, with up to 0.1 mA/cm2 measured under mild illumination. Collectively these optical properties make CAS NCs an excellent new candidate for both thin film and hybrid solar cells and as strong NIR absorbers in general.
- Van Embden, Joel,Latham, Kay,Duffy, Noel W.,Tachibana, Yasuhiro
-
supporting information
p. 11562 - 11571
(2013/09/02)
-
- Crystal structures of EuLnCuS3 (Ln = Nd and Sm)1
-
The compound sulfides EuLnCuS3 (Ln = Nd and Sm) were obtained for the first time. Their crys- tal structures were determined from X-ray powder diffraction data. The crystals of both compounds are orthorhombic (space group Pnma). The compound EuNdCuS3 is isostructural with BaLaCuS 3; the unit cell parameters are a = 11.0438(2) ?, b = 4.0660(1) ?, c = 11.4149(4) ?. The compound EuSmCuS3 is isostruc- tural with Eu2CuS3; the unit cell parameters are a = 10.4202(2) ?, b = 3.9701(1) ?, c = 12.8022(2) ?. Pleiades Publishing, Ltd., 2012.
- Ruseikina,Solovyov,Molokeev,Andreev
-
-
- Crystal structure of EuLaCuS3
-
The crystal structure of the EuLaCuS3complex sulfide synthesized for the first time has been solved by X-ray powder diffraction. Crystals are orthorhombic, space group Pnma, Ba2MnS3-type structure, a = 8.1297(3) ?, b = 4.0625(1) ?, c = 15.9810(4) ?, V = 527.80(3) ?3, Z = 4, and ρcalc = 5.669 g/cm 3. The La and Eu atoms are randomly disordered over two crystallographic positions with a coordination number of 7, and the Eu(La)-S bond lengths range from 2.892(6) to 3.078(6) ?. The CuS4 tetrahedra with Cu-S interatomic distances of 2.358(5)-2.40(1) ? form chains running along the b axis.
- Ruseikina,Solov'Ev,Andreev
-
p. 574 - 578
(2012/07/14)
-
- Controlling the crystallite size and influence of the film thickness on the optical and electrical characteristics of nanocrystalline Cu2S films
-
In this work, Cu2S nanocrystalline films have been successfully prepared using dip-coating technique. The stoichiometry and the structural characteristics of the prepared films were characterized by energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD), respectively. The surface morphology of the deposited Cu2S film was studied using both the scanning electron microscopy (SEM) and the atomic force microscopy (AFM). The SEM and AFM images indicate that the prepared Cu2S films are characterized by a well-dispersed and highly dense with spherical like-shaped aggregates of size in the nano scale. The optical absorption measurements indicate that the Cu2S nanoparticles have a direct band gap of 2.92 eV. The dispersion and absorption parameters such as the dispersion energy, oscillating energy, real and imaginary dielectric constants and dissipation factor were calculated within a wide wavelength range of the spectrum that indicates the suitability of the deposited films as solar absorber using this technique. The dark electrical resistivity (ρ) measurements were carried out at different temperatures in the range 312-440 K. These results confirm the semiconducting characteristic of the prepared Cu2S films. Moreover, two activation energies were obtained that indicate the presence of two dominating conduction mechanisms in these temperature ranges. The bulk electrical resistivity (ρB) and the mean free path (l 0) of charge carriers were estimated from the resistivity-thickness dependence. The heterojunction device of n-ZnCdS/p-Cu2S behaves good rectifying property. The photovoltaic characteristic of the heterojunction device using the current-voltage characteristic under illumination of 100 mW/cm2 was also observed. Discussion of the obtained results and their comparison with the previous published data were also considered.
- Rafea, M. Abdel,Farag,Roushdy
-
p. 257 - 266
(2012/03/13)
-
- Trialkylphosphine-stabilized copper(I) gallium(III) phenylchalcogenolate complexes: Crystal structures and generation of ternary semiconductors by thermolysis
-
A series of organometallic trialkylphosphine-stabilized copper gallium phenylchalcogenolate complexes [(R3P)mCu nMe2-xGa(EPh)n+x+1] (R = Me, Et, iPr, tBu; E = S, Se, Te; x = 0, 1) has been prepared and structurally characterized by X-ray diffraction. From their molecular structures three groups of compounds can be distinguished: ionic compounds, ring systems, and cage structures. All these complexes contain one gallium atom bound to one or two methyl groups, whereas the number of copper atoms, and therefore the nuclearity of the complexes, is variable and depends mainly on size and amount of phosphine ligand used in synthesis. The Ga-E bonds are relatively rigid, in contrast to flexible Cu-E bonds. The lengths of the latter are controlled by the coordination number and steric influences. The Ga-E bond lengths depend systematically on the number of methyl groups bound to the gallium atom, with somewhat shorter bonds in monomethyl compounds compared to dimethyl compounds. Quantum chemical computations reproduce this trend and show furthermore that the rotation of one phenyl group around the Ga-E bond is a low energy process with two distinct minima, corresponding to two different conformations found experimentally. Mixtures of different types of chalcogen atoms on molecular scale are possible, and then ligand exchange reactions in solution lead to mixed site occupation. In thermogravimetric studies the complexes were converted into the ternary semiconductors CuGaE2. The thermolysis reaction is completed at temperatures between 250 and 400 °C, typically with lower temperatures for the heavier chalcogens. Because of significant release of Me3Ga during the thermolysis process, and especially in case of copper excess in the precursor complexes, binary copper chalcogenides are obtained as additional thermolysis products. Quaternary semiconductors can be obtained from mixed chalcogen precursors.
- Kluge, Oliver,Krautscheid, Harald
-
p. 6655 - 6666
(2012/08/08)
-
- Kinetics of the interaction of iron, copper, and nickel sulfides with a sodium nitrate-sodium carbonate mixture
-
The interaction of FeS2, Cu2S, and Ni 3S2 with sodium nitrate and sodium carbonate between 573 and 973 K has been investigated by chemical analysis, X-ray diffraction, electron probe X-ray microanalysis, and thermal analysis. The kinetic limitations in these reactions are due to the formation of a passivating layer of reaction products on metal sulfide particles. The solid products of the reactions are sodium sulfate, Fe2O3, CuO, NiO, and copper metal. Pleiades Publishing, Ltd., 2011.
- Bogorodskii,Rybkin,Barankevich
-
p. 831 - 834
(2012/03/12)
-
- Phase diagrams of sections in the EuS-Cu2S-Nd2S 3 system
-
Phase equilibria in the EuS-Cu2S-Nd2S3 system were studied in an isothermal (970 K) section and NdCuS2-EuS and Cu2S-EuNdCuS3 polythermal sections. The complex sulfide EuNdCuS3 has an orthorhombic crystal lattice (space group Pnma; a = 1.10438(2) nm, b = 0.40660(1) nm, c = 1.14149(4) nm), is isostructural to BaLaCuS3, and melts incongruently at 1470 K: EuNdCuS3 (0.50 EuS; 0.50 NdCuS2) ai 0.18 EuS ss (0.88 EuS; 0.12 NdCuS 2) + 0.82 L (0.415 EuS; 0.585 NdCuS2); ΔH = 17.8 kJ/mol. Within the range 0.5 mol % EuS, EuNdCuS3-based solid solutions were not found. At 970 K, the tie lines pass from the compound EuNdCuS3 to Cu2S, EuS, NdCuS2, and EuNd 2S4 phases and lie between the NdCuS2 phase and solid solutions (ss) of γ-Nd2S3 with EuNd 2S4. Eutectics are formed between the compounds NdCuS 2 and EuNdCuS3 at 32.0 mol % EuS T = 1318 K and between the compounds Cu2S and EuNdCuS3 at 20.5 mol % EuNdCuS 3 and T = 1142 K. Five main subordinate triangles were identified in the system.
- Andreev,Ruseikina,Solov'Ev
-
p. 792 - 797
(2011/08/03)
-
- Luminescence and thermal behavior of copper (I) complexes with heterocyclic thiones. Part II: Cationic complexes
-
Copper (I) halide complexes formulated as [(L) 2Cu(μ2-L)2Cu(L)2]2+ 2Χ-, (X = Cl, Br and L = pyridine-2-thione (py2SH) or 4,6-dimethylpyrimidine-2-thione (dmpymtH)) were prepared, and their photoluminescence and thermal properties were investigated. The complexes are strongly emissive in the solid state, with the emissions being dominated by large Stokes shifts (>200 nm), which are depending on both the heterocyclic thione and the nature of the halogen. These emissions can be assigned to MLCT with some mixing of the halide-to-ligand (XL) CT characters. Simultaneous TG/DTG-DTA technique was used for two complexes with the dmpymtH ligand to determine their thermal degradation, which was found to be very complicated. In inert atmosphere the residues at 1,000 °C (verified with PXRD) were mainly Cu2S, while at 1,300 °C a mixture of Cu2S and Cu. In oxygen atmosphere the residues were CuO.
- Aslanidis,Chrissafis,Lalia-Kantouri
-
p. 797 - 803
(2011/04/27)
-
- Luminescence and thermal behavior by simultaneous TG/DTG-DTA coupled with MS of neutral copper (I) complexes with heterocyclic thiones
-
Copper(I) halide complexes formulated as [(L)CuX(μ2-L) 2CuX(L)] (X = Cl, Br and L = pyridine-2-thione (py2SH), or 4,6-dimethylpyrimidine-2-thione (dmpymtH)) were prepared, and their photoluminescence and thermal properties were investigated. The complexes are strongly emissive in the solid state, with the emissions being dominated by large Stokes shifts (>200 nm), which are depending on both the heterocyclic thione and the nature of the halogen. These emissions can be assigned to MLCT with some mixing of the halide-to-ligand (XL) CT characters. Simultaneous TG/DTG-DTA technique, coupled with MS for the analysis of the gaseous decomposition products, was used for two complexes with the dmpymtH ligand to determine their thermal degradation, which was found to be very complicated. In inert atmosphere the residues at 1,000 °C (verified with PXRD) were a mixture of Cu2S and CuX, while at 1,300 °C a mixture of Cu 2S and Cu. In oxygen atmosphere the residues were CuO.
- Aslanidis,Gaki,Chrissafis,Lalia-Kantouri
-
p. 525 - 531
(2011/04/18)
-
- Synthesis and properties of a Cu4(SCN)4 cubane cluster-based coordination polymer with a diamond net
-
A triply-interpenetrating diamondoid coordination polymer [Cu 4(SCN)4(tpom)]·2H2O (1, tpom = tetrakis(4-pyridyloxymethylene)methane) was prepared, which is built from an unprecedented pseudohalide cubane cluster Cu4(SCN)4 and tetrahedral tpom ligand. 1 exhibits high thermal stability and temperature-dependent photoluminescence behaviors resembling those of Cu 4Cl4 complexes.
- Ren, Shi-Bin,Zhou, Le,Zhang, Jun,Li, Cheng-Hui,Li, Yi-Zhi,Du, Hong-Bin,You, Xiao-Zeng
-
p. 558 - 561
(2011/05/02)
-
- Synthesis of nanostructured CuxS thin films by chemical route at room temperature and investigation of their size dependent physical properties
-
Nanostructured semiconductors show very interesting physical properties than bulk crystal due to size effects that arises because of quantum confinement of the electronic states. Using cupric acetate and sodium thiosulphate as cationic and anionic precursor, nanostructured Cu2S thin films were successfully prepared at room temperature by chemical bath deposition technique. By varying the deposition time from 9 to 24 h, the Cu2S films of thickness 70-233 nm were prepared. The different characterization methods such as X-ray diffraction (XRD), scanning electron microscopy (SEM), optical absorption and electrical resistivity measurement techniques were used to investigate size dependent properties of Cu2S thin films. As thickness increases, the hexagonal covellite phase of CuS observed at thickness 70 nm gets converted to monoclinic chalcosite phase of Cu2S. The resistivity and activation energy is found to be thickness dependent. The optical band-gap energy increases from 2.48 to 2.90 eV as thickness decreases from 233 to 70 nm. The influence of film thickness on carrier concentration, mobility and thermo-emf is reported.
- Ubale,Choudhari,Kantale,Mitkari,Nikam,Gawande,Patil
-
p. 9249 - 9254
(2011/10/11)
-
- Transformative two-dimensional layered nanocrystals
-
Regioselective chemical reactions and structural transformations of two-dimensional (2D) layered transition-metal chalcogenide (TMC) nanocrystals are described. Upon exposure of 2D TiS2 nanodiscs to a chemical stimulus, such as Cu ion, selective chemical reaction begins to occur at the peripheral edges. This edge reaction is followed by ion diffusion, which is facilitated by interlayer nanochannels and leads to the formation of a heteroepitaxial TiS2-Cu2S intermediate. These processes eventually result in the generation of a single-crystalline, double-convex toroidal Cu2S nanostructure. Such 2D regioselective chemical reactions also take place when other ionic reactants are used. The observations made and chemical principles uncovered in this effort indicate that a general approach exists for building various toroidal nanocrystals of substances such as Ag2S, MnS, and CdS.
- Jeong, Sohee,Han, Jae Hyo,Jang, Jung-Tak,Seo, Jung-Wook,Kim, Jin-Gyu,Cheon, Jinwoo
-
p. 14500 - 14503
(2011/10/17)
-
- Negative differential resistance and resistive switching behaviors in Cu2 S nanowire devices
-
Two-terminal devices of Cu2 S/ZnO core/shell nanowires were fabricated and measured. Forward bias sweeping produced a rectified I-V characteristic of a diode, with turn-on voltages varying from 150 to 300 mV. The turn-on voltages depended on the rate at which the bias was varied. When the bias scan was reversed, a resistive switching (RS) behavior was observed. A low-resistance state was measured, and the diode characteristic diminished. At -50 to -150 mV, negative differential resistance (NDR) was observed, after which the diode behavior was restored. This phenomenon was explained using the diffusion of Cu+ within Cu2 S. ZnO acted to limit RS to the positive bias range and NDR to the negative bias range.
- Liu, Xiaohua,Mayer, Matthew T.,Wang, Dunwei
-
-
- Solvothermal synthesis of copper sulfide semiconductor micro/nanostructures
-
Covellite copper sulfide (CuS) micro/nanometer crystals in the shape of hierarchical doughnut-shaped, superstructured spheric-shaped and flowerlike architectures congregated from those nanoplates with the thickness of 20-100 nm have been prepared by a solvothermal method. The as-obtained CuS products were characterized by means of scanning electron microscopy (SEM), X-ray diffractometry (XRD) and energy-dispersive X-ray spectroscopy (EDS). A systematic investigation has been carried out to understand the factors influencing the evolution of CuS particle morphology which found to be predominant by solvent, surfactant, sulfur resource and copper salt. The possible formation mechanism for the nanostructure formation was also discussed. These CuS products show potential applications in solar cell, photothermal conversion and chemical sensor.
- Liu, Jun,Xue, Dongfeng
-
p. 309 - 313
(2010/06/15)
-
- Synthesis and shape control of CuInS2 nanoparticles
-
Cu2S-CuInS2 hybrid nanostructures as well as pure CuInS2 (CIS) nanocrystals were synthesized by methods of colloidal chemistry. The structure, the shape and the composition of these nanomaterials were investigated with transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX). By changing the reaction conditions, CuInS2 nanorods with different aspect ratio, dimeric nanorods as well as hexagonal discs and P-shaped particles could be synthesized. Under our reaction conditions, CIS nanoparticles crystallize in the hexagonal wurtzite structure, as confirmed by Rietveld analysis of the X-ray diffraction patterns. The formation of Cu2S-CuInS2 hybrid nanostructures turned out to be an essential intermediate step in the growth of CIS nanoparticles, the copper sulphide part of the hybrid material playing an important role in the shape control of the CIS nanocrystals. By a treatment of Cu2S-CuInS2 with 1,10-phenanthroline, Cu2S parts of the hybrid nanostructures could be removed, and pure CIS nanoparticles with shapes not accessible with other methods can be obtained. Our synthetic procedure turned out to be suitable to synthesize also other compounds, like CuInS2-ZnS alloys, and to modify, in this way, the optical properties of the nanocrystals.
- Kruszynska, Marta,Borchert, Holger,Parisi, Juergen,Kolny-Olesiak, Joanna
-
p. 15976 - 15986
(2011/01/08)
-
