cas 7440-18-8, Ruthenium | Articles data

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REACTION OF Ru3(CO)12 WITH STYRENE
The reaction of styrene with Ru3(CO)12 yields the known complex Ru4(CO)12(PhC=CH) and the new cluster Ru4(CO)9(PhC=CH)(PhEt), in which a second molecule of styrene is hydrogenated and η6-bonded.
Johnson, Brian F. G.,Lewis, Jack,Aime, Silvio,Milone, Luciano,Osella, Domenico
p. 247 - 252
(1982)
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Electrooxidation of methanol on upd-Ru and upd-Sn modified Pt electrodes
The electrochemical oxidation of methanol has been investigated on underpotentially deposited-ruthenium-modified platinum electrode (upd-Ru/Pt) and on underpotentially deposited-tin-modified platinum electrode (upd-Sn/Pt). The submonolayers of upd-Ru and upd-Sn on a Pt electrode increased the rate of methanol electrooxidation several times as large as that on a pure Pt electrode. The best performance for methanol electrooxidation was obtained on a ternary platinum based catalyst modified by upd-Ru and upd-Sn simultaneously. The influence of the submonolayers of upd-Ru adatoms and upd-Sn adatoms on the oxidation of methanol in acid has been investigated. The effect of Ru on methanol electrooxidation lies on the distribution of Ru adatoms on a Pt surface. It has been shown that as long as the amount of upd-Ru deposits were controlled in a proper range, upd-Ru deposits would enhance the methanol oxidation obtained on a Pt electrode at whichever deposition potential the upd-Ru deposits were obtained. The effects of tin are sensible to the potential range. The enhancement effect of upd-Sn adatoms for the oxidation of methanol will disappear as the electrode potential is beyond a certain value. It is speculated that there exists a synergetic effect on the Pt electrode as adatoms Ru and Sn participate simultaneously in the methanol oxidation.
Wei,Li,Luo,Yan,Sun,Yin,Shen
p. 26055 - 26061
(2006)
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PHOTODEPOSITION OF Ru ON InP AND GaInPAs. CATALYTIC AND ELECTRONIC PROPERTIES.
The authors restrict this investigation to Ru/InP and Ru/GaInPAs contacts. The large grain polycrystalline quaternary semiconductor has been chosen because of differences in surface chemistry. Experimental data show that the typical current enhancement upon metallization is found. The increase in catalytic activity is larger for InP. A somewhat lower overall photoactivity is noted for GaInPAs.
Lewerenz,Michaelis
p. 913 - 916
(1988)
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A nonelectrochemical reductive deposition of ruthenium adatoms onto nanoparticle platinum: Anode catalysts for a series of direct methanol fuel cells
The surface of Pt nanoparticles was cleaned and saturated with hydrogen by treatment first with a 3% aqueous solution of H2O2 and then with hydrogen gas under water at room temperature. Reaction between the surface hydrogen and aqueous RuCl3 deposited 0.18 surface equivalents of Ruad onto the Pt nanoparticles. The deposition was repeated several times, with each reaction depositing ～0.18 surface equivalents more Ruad onto the Pt-Ruad nanoparticles. The resulting Pt-Ruad nanoparticles were analysed using cyclic voltammetry, CO stripping voltammetry, and as catalysts for electrooxidation of MeOH in three-electrode experiments and in prototype direct methanol fuel cells. The optimum surface coverage (θRu) for electrooxidation of MeOH was ～ 0.33 under these conditions.
Cao, Dianxue,Bergens, Steven H.
p. 4021 - 4031
(2003)
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Electrically benign Ru wet etching method for fabricating Ru/TiO 2 /Ru capacitor
Ru top electrode etching techniques for Ru/Ti O2 /Ru (RTR) thin film capacitor fabrication were examined. A dry etching process using a plasma mixture of O2, Cl2, and Ar gases deteriorated the leakage current properties significantly, which were not recovered by postannealing processes. The surface roughness was not a critical factor in determining the leakage characteristics. The etching damage along the etched edges was not the main cause of the leakage degradation but it was observed over the entire area, which was confirmed according to a comparison of capacitors with different perimeter/area ratios. For the wet etching of Ru films, the etch rates were evaluated using a periodic acid solution at various concentrations at 60°C. The Ru films etched using a 14 wt % periodic acid solution showed a moderate etch rate and a reasonable etching selectivity on the Ti O2 and Al2 O3 films. The as-wet-etched RTR capacitors showed a lower leakage current level than the dry-etched capacitors. Furthermore, the electrical properties of the wet-etched capacitor were improved significantly by a postannealing process.
Lee, Sang Young,Kim, Seong Keun,Kim, Kyung Min,Choi, Gyu-Jin,Han, Jeong Hwan,Hwang, Cheol Seong
p. G47-G51
(2011)
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Thermodynamic calculations and metallorganic chemical vapor deposition of ruthenium thin films using bis(ethyl-π-cyclopentadienyl)Ru for memory applications
The equilibrium concentrations of the various gaseous and solid phases in metallorganic chemical vapor deposition of Ru thin films were calculated in the experimentally relevant temperature and oxygen partial pressure ranges. Although thermal decomposition of the precursor, bis(ethyl-π-cyclopentadienyl)Ru [Ru(EtCp)2] required a sufficient amount of oxygen, experimental results showed that up to a certain concentration of oxygen, Ru metal was deposited without any detectable RuO2 impurity. Thermodynamic calculations showed that all the supplied oxygen was consumed to oxidize carbon and hydrogen, cracked from the precursor ligand, rather than Ru. Thus, metal films could be obtained. There was an optimum oxygen-to-precursor ratio at which the pure Ru phase could be obtained with minimum generation of not only carbon and RuO2 but also detrimental hydrogen. Ru thin films with minimal carbon and RuO2 contamination could be obtained by optimization of the oxygen supply at a low deposition temperature at 300°C.
Kang, Sang Yeol,Choi, Kook Hyun,Lee, Seok Kiu,Hwang, Cheol Seong,Kim, Hyeong Joon
p. 1161 - 1167
(2000)
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Heterometallic complexes of ruthenium and lanthanides (Ce, Pr, Nd, Eu) with NO2 bridges - Synthesis, structures, properties
Five new heterometallic complexes with a {Ln[RuNO(μ-NO2) 4(μ3-OH)]2Ln} (Ln = Ce, Pr, Nd, Eu) core were prepared by reaction of Na2[RuNO(NO2)4OH] and lanthanide nitrates in the presence of pyridine. The crystal structures of the obtained compounds were determined by single-crystal X-ray analysis. In all complexes, Ru and Ln atoms are connected by N,O-bridging nitrite groups and OH groups. The coordination environment of Ln3+ is completed by oxygen atoms of nitrate ions and water molecules and by nitrogen atoms of pyridine molecules. Magnetic interactions between lanthanide atoms become apparent at temperatures lower than 40-50 K, and at temperatures higher than 100 K, the dependencies of the magnetic susceptibilities of the complexes are well explained by the presence of two noninteracting paramagnetic centers. Thermal decomposition of the investigated complexes in an inert atmosphere results in a mixture of metallic ruthenium and the corresponding lanthanide oxide. Formation of mixed oxide phases RuPrOx was also detected after decomposition of the praseodymium complex. The reaction of lanthanide (Ce, Pr, Nd, Eu) nitrates with Na2[RuNO(NO2)4OH] in the presence of pyridine results in the formation of tetranuclear heterometallic complexes. The crystal structures, thermal, and magnetic properties of the obtained compounds are reported. Copyright
Borodin,Kostin,Plusnin,Filatov,Bogomyakov,Kuratieva
p. 2298 - 2304
(2012)
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Sol-gel synthesis of hydrous ruthenium oxide nanonetworks from 1,2-epoxides
Hydrous ruthenium oxide (RuO2·xH2O) xerogels were synthesized through the addition of a 1,2-epoxide, propylene oxide, to commercial hydrated ruthenium chloride, RuCl3·xH2O, in ethanol. After a blue-black monolithic gel formed in 4 h, the samples were allowed to age for 24 h and were dried in ambient conditions. The dried samples were then characterized by XPS, XRD, DTA and TGA. XPS showed the Ru(3d5/2) peak at a binding energy of 281.7 eV, corresponding to that of hydrous ruthenium oxide. XRD data revealed the synthesized material as amorphous. Heating the sample in inert atmospheres caused the complete reduction of the oxide to the zero-valent state, whereas heating the sample in air resulted in both crystalline anhydrous RuO2 and zero-valent ruthenium, depending on the method of heating. DTA traces showed an endotherm ending at 150 °C, corresponding to the loss of coordinated water, as well as two higher temperature crystallization exotherms when the sample was heated in both inert and oxygen-rich atmospheres. TGA runs also confirmed the complete reduction of the hydrous oxide when heated in nitrogen below 270 °C and the formation of anhydrous ruthenium oxide when heated in air, confirming the XRD results.
Walker, Jeremy,Bruce King,Tannenbaum, Rina
p. 2290 - 2297
(2007)
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Spectral, thermal and biological activity studies on ruthenium(II) complexes with some pyridylamines
Complexes resulted from the interaction of [Ph3P] 3RuCl2 with 2-aminoethylpyridine (aepy), 2-hydrazinopyridine (hzpy) and dipicolylamine (dpa) with KPF6 have been isolated from ethanol. The structures of the com
Omar
p. 607 - 615
(2009)
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PEALD of a ruthenium adhesion layer for copper interconnects
Ruthenium thin films were produced by plasma-enhanced atomic layer deposition (PEALD) using an alternating supply of bis(ethylcyclopentadienyl)ruthenium [Ru(EtCp)2] and NH3 plasma at a deposition temperature of 270°C. The film thickness per cycle was self-limited at 0.038 nm/cycle, which was thinner than the thickness obtained from the conventional ALD using oxygen instead of NH3 plasma. The ruthenium thin film prepared with PEALD had a preferential orientation toward (002), and it was progressively promoted with NH3 plasma power. The PEALD of ruthenium shows a merit in controlling ultrathin film thickness with less than 2 nm more precisely and more easily than the conventional ALD, due to the reduced transient period at the initial film growth stage. Also, ruthenium thin film improved the interfacial adhesion of metallorganic chemical vapor deposited copper to diffusion barrier metals by forming Cu-Ru chemical bonds at the interface without degrading the film resistivity of copper.
Kwon, Oh-Kyum,Kwon, Se-Hun,Park, Hyoung-Sang,Kang, Sang-Won
p. C753-C756
(2004)
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CHEMICAL VAPOR DEPOSITION OF RUTHENIUM AND RUTHENIUM DIOXIDE FILMS.
The preparation of Ru and RuO//2 thin films by organometallic chemical vapor deposition and an investigation of the films' properties are reported. Ru is of interest for metallization in integrated circuit fabrication because its thermodynamically stable oxide, RuO//2, also exhibits metallic conductivity. As a result, oxidation during processing of Ru is a less critical concern than in current metallization technology. Taking advantage of the benefits of chemical vapor deposition, such as conformal coverage and low temperature, damage-free deposition, we have deposited Ru, RuO//2, and Ru/RuO//2 by pyrolysis of three organoruthenium complexes. Films of a given phase composition were deposited under a wide variety of conditions and exhibited large variations in electrical resistivity and carbon content.
Green,Gross,Papa,Schnoes,Brasen
p. 2677 - 2685
(1985)
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The Synthesis of by the Carbonylation of and the Reactions of the Pentanuclear Cluster with a Variety of Small Molecules: the X-Ray Structure Analyses of , , , , and
The hexaruthenium cluster reacts with CO at 70 deg C and 80 atm to produce (1) and .Complex (1) crystallises in space group P21/c with a = 16.448(3), b = 14.274(2), c = 20.834(4) Angstroem, β = 91.36(2) deg, and Z = 8.The structure was found to be isomorphous with the analogue , and was refined to R = 0.051 for 3 256 diffractometer data.The five Ru atoms adopt a square-pyramidal geometry with an exposed carbido-atom lying 0.11(2) Angstroem beneath the basal plane.Reaction of complex (1) with the nitrogen-donor ligand MeCN yields the adduct (2) which exhibits a bridged butterfly arrangement of metal atoms with a central carbido-atom.The complex crystallises in space group P21/n with a = 14.116(6), b = 18.167(7), c = 10.276(4) Angstroem, β = 95.14(3) deg, and Z = 4; the structure was solved by direct methods and difference techniques and refined to R = 0.047 for 1 604 diffractometer data.Reactions of complex (1) with tertiary phosphine ligands PR3 or Ph2P(CH2)nPPh2 produce the substituted complexes 15-m(PR3)m> or nPPh2>> .The structures of these complexes are closely related to that of (1).Complex (3a) crystallises in space group Pn with a = 9.953(2), b = 12.247(2), c = 14.703(3) Angstroem, β = 91.23(2) deg, and Z = 2, (3b) in space group P21/c with a = 15.923(4), b = 12.494(3), c = 25.210(7) Angstroem, β = 93.28(2) deg, and Z = 4.Both structures were solved by a combination of direct methods and Fourier techniques and were refined to R = 0.021 for 3 305 reflections (3a) and R = 0.039 for 4 127 reflections (3b), respectively.Hydrogenation of (6) gives the dihydro-complex > which crystallises in space group P21 with a = 12.210(4), b = 18.602(6), c = 18.409(6) Angstroem, β = 97.63(2) deg, and Z = 4.The structure was solved using the same techniques as the other complexes and refined to R = 0.064 for 3 510 diffractometer data.Treatment of complex (1) with halide ions gives the anionic clusters (1-) (X = F, Cl, Br, or I) whose structures are similar to that of (2).Protonation of these anions gives the monohydrido-clusters .With Cl2 and Br2 complex (1) undergoes fragmentation to give dimers (X = Cl or Br); in contrast, reaction with I2 gives .
Johnson, Brian F. G.,Lewis, Jack,Nicholls, J. Nicola,Puga, Jose,Raithby, Paul R.,Rosales, Maria J.
p. 277 - 290
(1983)
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Regulative Electronic States around Ruthenium/Ruthenium Disulphide Heterointerfaces for Efficient Water Splitting in Acidic Media
Theoretical calculations unveil the charge redistribution over abundant interfaces and the enhanced electronic states of Ru/RuS2 heterostructure. The resulting surface electron-deficient Ru sites display optimized adsorption behavior toward diverse reaction intermediates, thereby reducing the thermodynamic energy barriers. Experimentally, for the first time the laminar Ru/RuS2 heterostructure is rationally engineered by virtue of the synchronous reduction and sulfurization under eutectic salt system. Impressively, it exhibits extremely high catalytic activity for both OER (201 mV @ 10 mA cm?2) and HER (45 mV @ 10 mA cm?2) in acidic media due to favorable kinetics and excellent specific activity, consequently leading to a terrific performance in acidic overall water splitting devices (1.501 V @ 10 mA cm?2). The in-depth insight into the internal activity origin of interfacial effect could offer precise guidance for the rational establishment of hybrid interfaces.
Chen, Ding,Gong, Lei,Guo, Yao,Liu, Fang,Luo, Jiahuan,Mu, Shichun,Shi, Wenjie,Wang, Pengyan,Wu, Jinsong,Xu, Hanwen,Yang, Yue,Zhang, Chengtian,Zhu, Jiawei
p. 12328 - 12334
(2021)
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Spectroscopic study of the electronic interactions in Ru/TiO2 HDS catalysts
The characteristics of Ru/TiO2 catalysts sulfided at temperatures from 573 to 873 K were studied by TPR-S, XRD, electron microscopy, EPR, and UV-Visible-NIR. It was found that the structure of the ruthenium sulfided phase formed at the differen
Castillo-Villalon, Perla,Ramirez, Jorge
p. 39 - 48
(2009)
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Improvements in growth behavior of CVD Ru films on film substrates for memory capacitor integration
Ru thin films were grown by metallorganic chemical vapor deposition using a cyclopentadienylpropylcyclopentadienlylruthenium(II) on the Ta 2O5, TiN, Si3N4, SiO2, TiO2 thin-film substrates and their nucleation and growth behaviors were investigated. It was observed that the bonding type between atoms of the substrate thin films has a profound effect on the nucleation behaviors. The more ionic the bonding, the smaller the nucleation barrier and smoother Ru films were obtained. The poor nucleation property of Ru films on TiN, which has a covalent bonding nature, was successfully improved by the Ar-plasma treatment on TiN substrate prior to the deposition of Ru film. It was found that the Ar plasma treatment selectively removes N ions from the surface and made the TiN surface more metallic or ionic (due to the residual Ti-O bonding) and reduced the nucleation barrier. Furthermore, oxidation resistance of Ru/TiN layers was improved by H2 annealing due to the densification of the Ru films. 2004 The Electrochemical Society. All rights reserved.
Kang, Sang Yeol,Hwang, Cheol Seong,Kim, Hyeong Joon
p. C15-C19
(2005)
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On the nature of the active state of supported ruthenium catalysts used for the oxidation of carbon monoxide: Steady-state and transient kinetics combined with in situ infrared spectroscopy
The oxidation of CO over Ru/MgO and Ru/SiO2 catalysts was used as a simple model reaction to derive turnover frequencies at atmospheric pressure, which were observed to agree with kinetic data obtained under high-vacuum conditions with supported ruthenium catalysts and the RuO 2(110) single-crystal surface. Thus, it was possible to bridge both the pressure and the materials gap. However, a partial deactivation was observed initially, which was identified as an activated process, both under net reducing and net oxidizing conditions. Temperature-programmed reduction (TPR) experiments were performed subsequently in the same reactor, to monitor the degree of oxidation, as a function of the reaction temperature and the CO/O 2 reactant feed ratio. Using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements, the structural changes of the ruthenium catalysts during the oxidation of CO were confirmed, under relevant reaction conditions. Under net reducing conditions, only domains of RuO2 seem to exist on the metallic ruthenium particles, whereas, under net oxidizing conditions, the ruthenium particles were fully oxidized to bulk RuO2 particles, which may expose less-active facets, such as the RuO2(100)-c(2 ?? 2) surface.
Assmann, Jens,Narkhede, Vijay,Khodeir, Lamma,Loì?ffler, Elke,Hinrichsen, Olaf,Birkner, Alexander,Over, Herbert,Muhler, Martin
p. 14634 - 14642
(2004)
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Carbon nanohorns grown from ruthenium nanoparticles
A nanoscale ruthenium/gold bimetallic cluster of clusters has been used as a molecular precursor to produce pure ruthenium nanoparticles (seeds) as catalysts for the growth of carbon nanohorns (CNHs).
Geng, Junfeng,Ducati, Caterina,Shephard, Douglas S.,Chhowalla, Manish,Johnson, Brian F. G.,Robertson, John
p. 1112 - 1113
(2002)
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Spectroscopic and thermal studies of chromium(III), molybdenum(VI) and ruthenium(0) complexes of maleic hydrazide
Interaction of maleic hydrazide (LH2) with [Cr(CO)6] in air at atmospheric pressure resulted in the formation of the complex [(LH)Cr(μ-O)2Cr(LH)] (1). Reaction of LH2 with [Mo(CO)6] in air also gave t
Mohamed, Hassan A.,Ali, Saadia A.,Ramadan, Ramadan M.
(2006)
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In situ STM study of nanosized Ru and Os islands spontaneously deposited on Pt(111) and Au(111) electrodes
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Strbac,Johnston,Lu,Crown,Wieckowski
p. 80 - 99
(2004)
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Thermal decomposition kinetics of some metal complexes of N,N-diethyl-N'-benzoylthiourea
Thcrmogravimctry (TG) and differential thermal analysis (DTA) were performed on the complexes with general formula (M(DEBT)n (where M=Fe, Co, Ni, Cu or Ru; n=2, or 3 and DEBT=N,N-di-cthyl-N'-bcnzoylthiourea). Derivative thermogravimctric (DTG) curves were also recorded in order to obtain decomposition data on the complexes. The complexes of Fe(III), Co(II), Ni(II), Cu(ll) and Ru(III) displayed two- or three-stage decomposition patterns when heated in a dynamic nitrogen atmosphere. Mass loss considerations relating to the decomposition stages indicated the conversion of the complexes to the sulfidcs or to the corresponding metal alone (Cu, Ru, NiS, CoS or FeS). Mathematical analysis of the TG and DTG data showed that the order of reaction varied between 0.395 and 0.973. Kinetic parameters such as the decomposition energy, the entropy of activation and the pre-exponcntial factor are reported.
Oezpozan,Arslan,Oezpozan,Merdivan,Kuelcue
p. 955 - 965
(2000)
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Preparation of Size-controlled Ruthenium Metal Particles on Carbon from Hydrido-carbonyl Cluster Complex
Monodispersed ultrafine particles of metallic ruthenium (1.3 and 2.1 nm in average diameters) were prepared by heating and stirring the mixed powders of hydrido-carbonyl cluster H4Ru4(CO)12 and microporous carbon at 433 K under H2 flow.It was revealed tha
Nakabayashi, Mamiko,Yamashita, Masaru,Saito, Yasukazu
p. 1275 - 1278
(1994)
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Electrochemical characterization of platinum-ruthenium nanoparticles prepared by water-in-oil microemulsion
The synthesis, physical characterization, decontamination and some electrocatalytic properties of PtRu nanoparticles prepared using the microemulsion method are reported. The nanoparticles are synthesized by reduction with sodium borohydride of H2PtCl6 and RuCl 3 in a water-in-oil microemulsion of water/polyethylenglycol- dodecylether (BRIJ 30)/n-heptane. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy dispersive analysis by X-rays (EDAX) experiments were carried out to characterize the single and bimetallic nanoparticles obtained. Cyclic voltammograms (CV) of clean nanoparticles were obtained after a controlled decontamination procedure of their surfaces. CO adsorption-oxidation and methanol electrooxidation were used as test reactions to check the electrocatalytic behaviour of the bimetallic nanoparticles. Pt 80Ru20 (nominal atomic composition) nanoparticles are the best electrocatalyst for both COad and methanol oxidation. All these results show that the microemulsion method can be used to produce bimetallic nanoparticles in a very easy way. The method can be very easily scaled-up for industrial use.
Solla-Gullón,Vidal-Iglesias,Montiel,Aldaz
p. 5079 - 5088
(2004)
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Synthesis, spectral and thermal studies of the sodium salts of some Ru(III) complexes with quinolone antibiotics
Solubilisation by salt formation is an effective method to increase the solubility of slightly soluble drugs, applied especially for the development of liquid formulations for parenteral administration. In the present study, this strategy is applied for new Ru(III) complexes with quinolone antibiotics, valuable for biological application such as anticancer activity. The parent compounds, formulated as RuCl3(HL)2(DMSO)m(H2O)n (HL: pipemidic acid, norfloxacin, ciprofloxacin, ofloxacin, levofloxacin, enrofloxacin, enoxacin), were transformed in their corresponding soluble sodium salts with general formula Na2RuCl3(L)2(DMSO)m(EtOH)n(H2O)p. The sodium salts have been characterised by elemental analysis and some spectrometric methods (IR, UV–Vis, mass spectra). The thermal behaviour of these newly compounds was studied by simultaneous TG/DTG/DTA analysis, and it was evidenced a higher thermal stability compared to that of the parent compounds. The thermal transformations occur in two or three steps and comprise solvent (solvation or coordination) elimination as well as oxidative degradation of quinolone derivatives. A mixture of ruthenium and sodium chloride was identified as final residue.
Badea, Mihaela,Olar, Rodica,Silvestro, Luigi,Maurer, Martin,Uivarosi, Valentina
p. 721 - 729
(2017)
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Thermodynamic stability of CaRuO3
The e.m.f. of the galvanic cell Pt, CaO, CaRuO3, Ru|15 CSZ|O2 (PO(2) = 0.21 atm), Pt was studied over the range 971-1312 K using 15wt.%CaO-stabilized ZrO2 (15 CSZ) as the solid electrolyte. This study yielded th
Mallika, C.,Sreedharan, O. M.
p. 273 - 278
(1991)
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Vapor deposition of pure ruthenium metal from ruthenocene
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Trent,Paris,Krause
p. 1057 - 1058
(1964)
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Ruthenium Bottom Electrode Prepared by Electroplating for a High Density DRAM Capacitor
The possibility of Ru electroplating for application as the bottom electrode in high density dynamic random access memory (DRAM) capacitors was investigated. Prior to Ru electroplating on a TiN substrate, HF cleaning and Pd activation were performed. Removal of Ti oxide from the TiN substrate by HF treatment enabled Pd activation, which enhanced the nucleation of Ru on TiN substrate. Optimized pretreatments led to a continuous Ru film deposition. The surface roughness was measured to be 4.4 nm at 45 nm Ru film on the bare substrate. Moreover Ru electroplating method was also applied to a capacitor node-type TiN wafer. The deposition rate of Ru on the patterned wafer was the same as that on a bare wafer. The film showed 93% step coverage and good adhesion, comparable to CVD Ru films.
Kwon, Oh Joong,Cha, Seung Hwan,Kim, Jae Jeong
p. C127-C132
(2004)
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Atomic Layer Deposition of Ruthenium Thin Films for Copper Glue Layer
Ruthenium thin films were produced by atomic layer deposition (ALD) using an alternating supply of bis(ethylcyclopentadienyl)ruthenium [Ru(EtCp) 2] and oxygen at a deposition temperature of 270°C. The relative ratio of the Ru(EtCp)2 adsorbed on the film surface to the oxygen partial pressure in the following oxygen pulse determines whether Ru or RuO 2 film was obtained. At the range with higher relative ratio the film was composed of ruthenium, but the film deposited at the lower range was revealed to be ruthenium oxide. In case of the ruthenium thin film, the film thickness per cycle was saturated at 0.15 nm/cycle, and its resistivity was about 15 μω cm. The impurities of carbon and oxygen were incorporated into the film with less than 2 atom %. It was also demonstrated that the ruthenium thin films prepared by ALD can be used as an excellent glue layer to improve the interfacial adhesion of metallorganic chemical vapor deposited copper to TiN. Secondary ion mass spectroscopy analysis showed that the ruthenium glue layer suppressed the interfacial contaminants, such as carbon and fluorine, which originated from the metallorganic precursors of copper.
Kwon, Oh-Kyum,Kim, Jae-Hoon,Park, Hyoung-Sang,Kang, Sang-Won
p. G109-G112
(2004)
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Electrochemical preparation of photosensitive porous n-type Si electrodes, modified with Pt and Ru nanoparticles
A novel electrochemical procedure for preparation of the very stable, thin modifying layer onto the n-type Si surface was elaborated. The modification consisted of platinum or/and ruthenium ultrafine particles etched into the porous Si film. A unique sequence of modifications was applied: at first the metal particles were evenly electrodeposited onto a flat silicon surface, and in the next electrochemical step the porous structure was produced. The platinum coverage and mean particle diameter were well controlled by the electrochemical programs. All the attempts and progress in modifications were monitored by scanning electron microscope (SEM) observations. Furthermore, the materials obtained were compared with the non-porous, Pt or/and Ru modified electrodes by testing them as anodes in the photoelectrochemical (PEC) cell with organic Br2/2Br- solution. In general, the porous photo-anodes gave higher output powers and the light-to-electricity conversion efficiencies. The best performance was observed for the PEC cell employing the porous anode with sequentially electrodeposited Ru and Pt particles, respectively (PS-Si/Ru/Pt).11 PS-Si means the porous silicon film; Si/Pt/Ru describes the sequence of metal depositions onto Si, in this case the Pt deposition is followed by the Ru deposition. This cell maintained good electrical parameter values during the 2-week tests, having a maximum output power equal to 0.23 mW/cm2 and a cell conversion efficiency of 8.5%. The PS-Si/Pt photo-anode gained 0.21 mW/cm2 and 7.8%, respectively.
Macherzynski,Milczarek,Mamykin,Romanyuk,Kasuya
p. 4395 - 4401
(2010)
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Hexaaquoruthenium(II)
The hexaaquoruthenium(II) ion has been separated and characterized in aqueous solution. The ion was formed by electrolytic reduction of ruthenium(III) at a controlled potential of -0.40 v. with respect to a saturated calomel electrode, using a mercury pool cathode. The only anions found which did not interfere with the formation of this ion were tetrafluoroborate and p-toluenesulfonate. In the presence of other anions, either oxidation or complexation of the ruthenium was found to take place. The charge on the ion was determined using ion-exchange methods. The oxidation state of the metal was verified by coulometry and titration of the ion with triiodide. The oxidation potential for the half-reaction Ru+2 → Ru+3 + e- was found to be -0.22 ± 0.03 v. by polarography.
Mercer,Buckley
p. 1692 - 1695
(1965)
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Calcium ruthenates: Determination of Gibbs energies of formation using electrochemical cells
Metallic Ru has been found to coexist separately with CaO, RuO2, and the interoxide phases, Ca2RuO4, Ca3Ru2O7, and CaRuO3, present along the pseudobinary system CaO-RuO2. The standard Gibbs energies of formation (Δf(ox)G°) of the three calcium ruthenates from their component oxides have been measured in the temperature range 925-1350 K using solid-state cells with yttria-stabilized zirconia as the electrolyte and Ru + RuO2 as the reference electrode. The standard Gibbs energies of formation (Δf(ox)G°) of the compounds can be represented by Ca2RuO4: Δf(ox)G°/J mol-1 = -38,340 - 6.611 T (±120), Ca3Ru2O7: Δf(ox)G°/J mol-1 = 75,910 - 11.26 T (±180), and CaRuO3: Δf(ox)G°/J mol-1 = -35,480-3,844 T (±70). The data for Ca2RuO4 corresponds to the stoichiometric composition, which has an orthorhombic structure, space group Pbca, with short c axis ( S form). The structural features of the ternary oxides responsible for their mild entropy stabilization are discussed. A three-dimensional oxygen potential diagram for the system Ca-Ru-O is developed as a function of composition and temperature from the results obtained. Using the Neumann-Kopp rule to estimate the heat capacity of the ternary oxides relative to their constituent binary oxides, the standard enthalpies of formation of the three calcium ruthenates from the elements and their standard entropies at 298.15 K are evaluated.
Jacob, K. Thomas,Lwin, Kay Thi,Waseda, Yoshio
p. E227-E232
(2003)
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A study of the complex composition of sulfamate ruthenium-plating electrolytes
Varying-with-time complex composition of a sulfamate ruthenium-plating electrolyte was studied. Recommendations are given concerning the working modes and adjustment conditions in prolonged operation of the electrolyte.
Karabanov,Lokshtanova
p. 1000 - 1003
(2008)
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Structure and reactivity of Ru nanoparticles supported on modified graphite surfaces: A study of the model catalysts for ammonia synthesis
Supported ruthenium metal catalysts have higher activity than traditional iron-based catalysts used industrially for ammonia synthesis. A study of a model Ru/C catalyst was carried out to advance the understanding of structure and reactivity correlations in this structure-sensitive reaction where dinitrogen dissociation is the rate-limiting step. Ru particles were grown by chemical vapor deposition (CVD) via a Ru3(CO)12 precursor on a highly oriented pyrolytic graphite (HOPG) surface modified with one-atomic-layer-deep holes mimicking activated carbon support. Scanning tunneling microscopy (STM) has been used to investigate the growth, structure, and morphology of the Ru particles. Thermal desorption of dissociatively adsorbed nitrogen has been used to evaluate the reactivity of the Ru/HOPG model catalysts. Two different Ru particle structures with different reactivities to N2 dissociation have been identified. The initial sticking coefficient for N2 dissociative adsorption on the Ru/HOPG model catalysts is ～10-6, 4 orders larger compared to that of Ru single-crystal surfaces.
Song, Zhen,Cai, Tanhong,Hanson, Jonathan C.,Rodriguez, Jose A.,Hrbek, Jan
p. 8576 - 8584
(2004)
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Characterization of Catalysts Derived from Oxidation of RuxThy Intermetallics
Ru methanation catalysts derived from oxidation of RuxThy intermetallics were characterized by X-ray photoelectron spectroscopy (ESCA), ion scattering spectroscopy (ISS), X-ray diffraction (XRD), BET surface area measurements, chemisorption, and gravimetric analysis.XRD measurements and gravimetric analysis indicated that all intermetallics were extensively decomposed by oxidation in air at 350 deg C.ESCA and ISS Ru/Th intensity ratio measurements showed that surface segregation of ThO2 occurred for all catalysts.The structure of the intermetallic-derived (IM) catalysts can best be described as Ru particles embedded in a ThO2-rich overlayer.Comparison of hydrogen and CO uptake with N2 BET surface area suggests that CO more accurately titrates surface Ru than does hydrogen.Extensive spillover of hydrogen from Ru to ThO2 was also observed for all IM catalysts.The catalysts were tested for CO hydrogenation; exceptionally high methane selectivity was observed for all catalysts.On the basis of CO chemisorption, the CO hydrogenation turnover frequency was comparable for all the IM catalysts.The CO hydrogenation activities and selectivities are discussed on the basis of the structure sensitivity of CO hydrogenation on Ru catalysts and the special morphology of the IM catalysts.
Huang, Chen-Shi,Houalla, Marwan,Hercules, David M.,Kibby, Charles L.,Petrakis, Leonidas
p. 6749 - 6753
(1990)
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Thermal stability of RuSr2GdCu2O8, Ru 1 - xSr2GdCu2O8 - y, RuO2
Thermal stability of RuSr2GdCu2O8, Ru 0.9Sr2GdCu2O8-y, and RuO2 powders in oxygen has been studied by thermogravimetry. Decomposition of RuSr2GdCu2O8 and Ru0.9Sr 2GdCu2O8-y samples in 0.85 bar of oxygen appears as a solid phase process at ～1050 °C. This is followed by peritectic decomposition with onset starting at ～1110 °C for the stoichiometric sample and at ～1090 °C for the Ru deficient one. We observed that sublimation of ruthenium oxide in 0.85 bar of oxygen starts at ～850 °C and sample's humidity significantly increases a sublimation rate. Enhanced sublimation above 1060 °C was observed for powder mixtures (RuO2+xCuO), x=0.1, 0.2, 0.5. Analysis of the sublimation process of these mixtures suggests existence of an unknown compound in Ru-Cu-O system with approximate composition Ru1-xCuxO2-y, xa synthetic route of rutenates and, in particular RuSr 2GdCu2O8 phase, eliminating Ru off-stoichiometry and phase separation, are discussed.
Matveev,Maljuk,Kulakov,Lin,Habermeier
p. 139 - 146
(2004)
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Vapor deposition of ruthenium from an amidinate precursor
Atomic layer deposition (ALD) and pulsed chemical vapor deposition (CVD) were used to make ruthenium (Ru) thin films from a volatile Ru amidinate precursor, bis (N, N′ -di-tert-butylacetamidinato)ruthenium(II) dicarbonyl. The CVD films were grown without any coreactant, while the ALD films used ammonia as a coreactant. The films are fine-grained polycrystalline ruthenium with high purity (a continuous, electrically conductive, pinhole-free film on tungsten nitride (WN) films even for films as thin as 2 nm. The resistivities of the films match those of pure sputtered ruthenium of the same thickness. Roughness is a second reagent, thereby avoiding damage to sensitive substrates. The ALD growth rate can reach 1.5 Acycle at a substrate temperature of 300°C.
Li, Huazhi,Farmer, Damon B.,Gordon, Roy G.,Lin, Youbo,Vlassak, Joost
p. D642-D647
(2007)
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In situ Ru K-edge EXAFS of CO adsorption on a Ru modified Pt/C fuel cell catalyst
The Ru-CO bond of CO adsorbed on a Ru modified Pt/C fuel cell catalyst has been directly probed by in situ EXAFS at the Ru K-edge, providing evidence of a CO:metal surface atom ratio greater than 1:1 and that CO is adsorbed at bridging sites associated wi
Rose, Abigail,Bilsborrow, Robert,King, Colin R.,Ravikumar,Qian, Yangdong,Wiltshire, Richard J.K.,Crabb, Eleanor M.,Russell, Andrea E.
p. 5262 - 5266
(2009)
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Preparation of Ru nanoparticles supported on γ-Al2O3 and its novel catalytic activity for ammonia synthesis
Uniform ruthenium metal nanoparticles with an average diameter of 5 nm were prepared and supported on γ-Al2O3 up to 6.3 wt%. The ruthenium nanoparticles were obtained by the reduction of RuCl3 in ethylene glycol. While maintaining their original morphology, more than 99% of the colloidal Ru nanoparticles, obtained were successfully supported on γ-Al2O3. The Ru/Al2O3 catalyst prepared from a metal colloid had an unusually high activity for ammonia synthesis. The rate of ammonia formation was at least 12 times higher than the rate of nonpromoted Ru/Al2O3 catalysts prepared by conventional methods, and at least 3.5 times higher than the promoted Cs, Rb, K, Ce, La, and Sm Ru/Al2O3 catalysts. Alumina was not expected to be an ideal support for ammonia synthesis because of its acidity, and thus the promotion by additives was considered necessary. The present investigation proves that alumina can be a suitable support for ammonia synthesis if ruthenium is supported on it as metal nanoparticles. The results point out the possibility that the active sites formed by conventional impregnation methods are significantly contaminated with the supports. In contrast, by keeping the interaction with the support at a minimum, the novel preparation method of the Ru/Al2O3 catalyst by Ru colloid deposition gives well-defined metal particles with high catalytic activity.
Miyazaki, Akane,Balint, Ioan,Aika, Ken-Ichi,Nakano, Yoshio
p. 364 - 371
(2001)
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Anodically formed oxide films and oxygen reduction on electrodeposited ruthenium in acid solution
The impedance of the anodically formed hydrous Ru oxide in the system Ru|oxide film|1 M HClO4 solution has been studied in the range of potentials where the electrode process occurs by a double electron and proton exchange between the oxide film and the solution. The results allowed us to clearly distinguish between the surface process at higher frequency and the bulk process at lower frequency. The high-frequency charging is found to be coupled to Faradaic charging at the film/solution interface. Evaluation of the impedance data at lower frequency, using diffusion equations for the finite boundary conditions, yields an effective proton diffusion coefficient to be 10 -10 to 10-11 cm2 s-1. Oxygen reduction on the spontaneously oxidized ruthenium electrode was discussed on the basis of a rotating ring-disk voltammetry.
Metiko?-Hukovi?,Babi?,Jovi?,Gruba?
p. 1157 - 1164
(2006)
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Characterisation of the Ru/MgF2 catalyst with adsorbed O2, NO, CO probe molecules by EPR and IR spectroscopy
Electron paramagnetic resonance (EPR) and infrared (IR) spectroscopy were used to study the formation of ruthenium and adsorbed species appearing on the catalyst during O2, NO, and CO adsorption at room temperature on 1 wt% Ru/MgF2 catalysts prepared from Ru3(CO)12 . Both EPR and IR results provided clear evidence for the interaction between surface ruthenium and probe molecules. No EPR signals due to ruthenium (Ru) species were recorded at 300 and 77 K after H2-reduction of the catalyst at 673 K. However, at 4.2 K a very weak EPR spectrum due to low-spin (4d5) Ru3+ complexes was detected. A weak anisotropic O2- radicals signal with g{divides}{divides}=2.017 and g⊥=2.003 superimposed on a broad (ΔBpp=120 mT), slightly asymmetric line at g=2.45(1) was identified after O2 admission to the reduced sample. Adsorption of NO gives only a broad, Gaussian-shaped EPR line at g=2.43(1) indicating that the admission of NO, similarly to O2 adsorption, brings about an oxidation of Ru species in the course of the NO decomposition reaction. Introduction of NO over the CO preadsorbed catalyst leads to EPR spectrum with parameters g⊥=1.996, g{divides}{divides}=1.895, and A⊥N=2.9 mT assigned to surface NO species associated with Ru ions. The IR spectra recorded after adsorption of NO or CO probe molecules showed the bands in the range of frequency characteristic of ruthenium nitrosyl, nitro, and nitrate/nitrite species and the bands characteristic of ruthenium mono-and multicarbonyls, respectively. Addition of CO after NO admission to the catalyst leads to appearance in the IR spectrum, beside the ones characteristic of NO adsorption, the bands which can be attributed to Ru-CO2 and Ru-NCO species, indicating that the reaction between NO and CO occurs. These species were also detected after CO adsorption followed by NO adsorption, additionally to the band at 1850 cm-1 being due to cis-type {A figure is presented} species.
Goslar,Wojciechowska,Zieliński
p. 1387 - 1393
(2006)
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Preparation and characterization of 4-Amino-2-Anilinopyridine and its chlorodiruthenium(III,II) complex
A new bridging agent, 4-Amino-2-Anilinopyridine (aap), was synthesized and used as an equatorial ligand in the preparation of a diruthenium complex (4,0) Ru2(aap)4Cl. Both the ligand and the diruthenium complex were characterized by thermal analysis, MALDI-TOF mass spectrometry, IR and NMR (1H and 13C) spectroscopy, and X-ray crystallography. The structural analysis revealed that the complex existed as a (4,0) isomer, in which the amino group on the pyridyl moiety was not involved in chemical bonding.
Naidu, Naga V.,Arman, Hadi,Deng, Yuanjian,Wei, Xin
p. 3006 - 3017
(2014)
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Direct regeneration of NADH on a ruthenium modified glassy carbon electrode
The regeneration of NADH in a batch electrochemical reactor using a ruthenium modified glassy carbon electrode (RuGC) has been investigated. The information on the structure of the electrode/electrolyte interface in the presence of NAD+ in the solution, the kinetics of NAD+ reduction, and the batch-electrolysis NADH regeneration has been obtained using electrochemical techniques of dc linear potential (LP) and constant potential (CA) polarization, ac differential capacitance (DC), and electrochemical impedance spectroscopy (EIS). It has been shown that the modification of GC by a sub-monolayer of Ru can provide an electrode surface capable of reducing NAD+ directly to NADH at a high yield of enzymatically active 1,4-NADH (96%). From the electrochemical point of view, the reaction is irreversible and occurs at high cathodic overpotentials, where the reaction rate is controlled by the surface diffusion of electroactive species. EIS measurements have shown that the electrode/electrolyte interface and the corresponding charge- and mass-transfer processes can be described by an electrical equivalent circuit composed of two time constants in parallel, with the additional contribution of a mass-transport Warburg impedance element. The time constant recorded at higher frequencies represents the response of a GC part of the electrode surface, while the lower-frequency time constant can be related to the response of Ru sites on the electrode surface. It has been determined that the NAD+ reduction reaction is of first order with respect to NAD+. The calculated apparent heterogeneous reaction rate constant values are rather low, which is due to the slow mass-transport of electroactive species at the electrode surface. The kinetic analysis has demonstrated that a very good agreement between the apparent heterogeneous reaction rate constant values calculated using three different experimental techniques is obtained.
Azem, Amir,Man, Felise,Omanovic, Sasha
p. 283 - 299
(2004)
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An evaluation of monovalent osmium supported by the PNP ligand environment
Nitrogen is essential to reaction of (PNP)OsI (PNP is N(SiMe 2CH2PtBu2)2) and Mg powder in THF, to give equimolar (PNP)OsH(N2) and hydrido carbene [(tBu2PCH2SiMe2)N(SiMe 2CH2PtBu(CMe2CH)]OsH. This reaction is attributed to H2 evolution from solid magnesium, rather than high energy H atom transfer between molecules, but relies also on the strong π-basicity of Os in favoring α-H migration from the metallated tBu group on Os to form the second product, the hydrido carbene species. The path to two different products begins because the simple N 2 adduct of (PNP)OsI undergoes spontaneous heterolytic H-C splitting of the tBu methyl group, to produce a secondary amine intermediate [(tBu2PCH2SiMe2)N(H)(SiMe 2CH2PtBu(CMe2CH2)] OsI(N2) which can then be dehydrohalogenated by Mg. The analogous reaction for (PNP)RuCl shows production of only (PNP)RuH(N2), with none of the hydride carbene dehydrogenation product. Comparative (Ru vs. Os) DFT calculations reveal the reaction steps where the Os analog is much more exothermic, accounting for certain reaction selectivities.
Tsvetkov, Nikolay,Fan, Hongjun,Caulton, Kenneth G.
p. 1105 - 1110
(2011)
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Formation of Ru nanocrystals by plasma enhanced atomic layer deposition for nonvolatile memory applications
The formation of Ru nanocrystals is demonstrated on a SiO2 substrate by plasma enhanced atomic layer deposition using diethylcyclopentadienyl ruthenium and NH3 plasma. The island growth of Ru was observed at the initial stages of the film formation up to a nominal thickness of 11.1 nm. A maximum Ru nanocrystal spatial density of 9.7 × 1011 /cm2 was achieved with an average size of 3.5 nm and standard deviation of the size of 20%. Electron charging/discharging effect in the Ru nanocrystals is demonstrated by measuring the flatband voltage shift in the capacitance-voltage measurement of metal-oxide-semiconductor memory capacitor structure.
Yim, Sung-Soo,Lee, Moon-Sang,Kim, Ki-Su,Kim, Ki-Bum
(2006)
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Tuning the selectivity of ruthenium nanoscale catalysts with functionalised ionic liquids: Hydrogenation of nitriles
Ruthenium nanoparticles prepared in nitrile-functionalised ionic liquids (ILs) display unusual selectivities toward the hydrogenation of nitrile containing aromatic compounds. In particular, a selective catalytic hydrogenative coupling of nitriles was obs
Prechtl, Martin H.G.,Scholten, Jackson D.,Dupont, Jairton
p. 74 - 78
(2009)
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Highly dispersed ultra-fine Ru nanoparticles anchored on nitrogen-doped carbon sheets for efficient hydrogen evolution reaction with a low overpotential
Development of highly efficient and costeffective hydrogen evolution reaction (HER) electrocatalyst that rivals benchmark Pt is highly desirable but challengeable. In this work, the integration of uniformly dispersed ultra-fine Ru nanoparticles with the nitrogen-doped carbon sheets (NCs) is reported as an efficient electrocatalyst. The Ru/NCs composite catalyst possesses abundant catalytic activity sites, and the synergy effect between Ru and NCs can modulate the electronic structure and adsorption of reaction intermediate to enhance the HER activity. Remarkably, the optimal 20% Ru/NCs catalyst delivers an overpotential of as low as 13 mV at the current density of 10 mA cm?2 and with a Tafel slope of 31.8 mV dec?1, which is superior to most of recently reported Ru-based electrocatalysts and even, superior to the state of the art Pt/C catalyst. This work provides an effective strategy for the development of ultra-efficient electrocatalyst for the water splitting in alkaline condition.
Gao, Menghan,Wang, Zhihong,Sun, Shichao,Jiang, Deli,Wei, Wenxian,Chen, Min
(2020/12/21)

Cobalt and ruthenium complexes with pyrimidine based schiff base: Synthesis, characterization, anticancer activities and electrochemotherapy efficiency
In this study, a new Schiff base ligand and its two M(II) complexes [CoCl·L(H2O)2]·2H2O, [RuCl(p-cymene)L] were synthesized. The structural features were confirmed from their micro analytical, IR, UV–Vis., 1H–13C NMR, TGA, X-ray diffraction analysis, mass spectral data and magnetic susceptibility measurements. The Co(II) and Ru(II) complexes displayed an octahedral geometry. In vitro anticancer activities of the Schiff base, Co(II) and Ru(II) complexes were evaluated on the human colon cancer cell line (Caco-2) and biocompatibility characteristics were determined in the L-929 (normal fibroblast cells) cell line by using the MTT assay. Furthermore, we examined the effectiveness of electrochemotherapy (ECT) on cytotoxic activities of these compounds in Caco-2 cancer cell line. According to the findings of the study, Co(II) and Ru(II) complexes showed considerable anticancer properties in the Caco-2 colon cancer cells; however, the ligand did not show significant anticancer activity. It was determined that the combined application of electroporation (EP)+complexes were much more effective than the application of complexes alone in the treatment of Caco-2 colon cancer cells. In a conclusion, the Co(II) and Ru(II) complexes, which showed significant anticancer activity in Caco-2 colon cancer cells, increased cytotoxicity levels by 2.07 and 2.12, respectively in their combined applications with EP. These complexes can be developed as chemotherapeutic agents for colon cancer treatment and can yield promising results when used in ECT.
Alan, Yusuf,Alk??, Mehmet E?ref,Buldurun, Kenan,Kele?temür, ünzile,Turan, Nevin
(2020/10/13)

Enhancing electrochemical nitrogen reduction with Ru nanowires: via the atomic decoration of Pt
Achieving an efficient electrochemical nitrogen reduction reaction (ENRR) remains a great challenge, demanding the development of a new strategy for ENRR catalyst engineering. Herein, we demonstrate a largely improved ENRR by the controlled engineering of Ru nanowires with atomic Pt decoration. Specifically, the readily synthesized Ru88Pt12 nanowires exhibit a high NH3 production rate of 47.1 μg h-1 mgcat-1 and faradaic efficiency of 8.9% at -0.2 V, which are 5.3 and 14.6 times higher than those values for Ru nanowires. They also show outstanding stability, as evidenced by the full preservation of the NH3 yield and faradaic efficiency even after 15 h of electrocatalysis. As revealed by theoretical investigations, the d-band center of Ru atoms is upshifted by the tensile strain due to the presence of Pt atoms, leading to the selective enhancement of N2 adsorption and the stabilization of N2H?. Such an atomic engineering method may be applied to precisely tailor other metal nanocatalysts for different applications.
An, Changhua,Chen, Peng,Yang, Liting,Zhang, Jichao,Zhang, Weiqing,Zhu, Junfa
supporting information
p. 25142 - 25147
(2020/12/25)

Soluble Cytotoxic Ruthenium(II) Complexes with 2-Hydrazinopyridine
New water soluble Ru(II) binary complex [Ru(C5H7N3)(X)(H2O)2] with 2-hydrazinopyridine and its ternary complexes with X = dichloride, oxalate, malonate or pyrophosphate ligands have been synthesized. The complexes have been characterized using elemental analyses, mass, IR, and UV-Vis. spectroscopies, cyclic voltammetry, magnetic susceptibility, and thermal analysis. The complexes are diamagnetic and the electronic spectral data showed that peaks are due to low spin octahedral Ru(II) complexes. The optimized structures of the complexes 1–4 indicate distorted octahedral geometry with bond angles around the ruthenium atom ranged from 80.44° to 99.64°. The values of the electronic energies (?635 to ?1145 a.u.), the highest occupied molecular orbital energies (?0.181 to 0.073 a.u.) and lowest unoccupied molecular orbital energies (?0.056 to 0.167 a.u.) indicate the stability of the complexes. The complexes are polarized as indicated from the dipole moment values (9.39–14.27 Debye). The complexes have noticeable cytotoxicity with IC50 (μM): 0.011–0.062 (HepG-2), 0.015–0.080 (MCF-7), 0.015–0.116 (HCT-116), and PC-3 (0.034–0.125).
Soliman,Attaby,Alajrawy,Majeed,Sahin,Varlikli
p. 742 - 754
(2019/07/16)

Holey Ruthenium Nanosheets with Moderate Aluminum Modulation toward Hydrogen Evolution
Theoretical calculations reveal that aluminum (Al) doping can effectively modulate the electronic structures of 2D ruthenium (Ru) catalysts. Moderate Al incorporation can endow Ru nanosheets with more delocalized electrons and optimal hydrogen adsorption Gibbs free energy, providing opportunities to achieve improved hydrogen evolution performance. Thus, Al-doped Ru nanosheets have been synthesized by a solvothermal strategy, in which they exhibit holey nanosheet structures and have more active sites exposed on the basal plane. The characterizations unraveling the Ru structure can be well maintained, and electrochemical measurements confirm the appropriate amount of Al modulation that can extremely enhance its hydrogen evolution activity.
Zhang, Hang,Liu, Qilong,Xu, Jie,Wei, Lingzhi,Liu, Qiangchun,Kong, Xiangkai
supporting information
p. 8267 - 8270
(2019/07/03)

Ice Melting to Release Reactants in Solution Syntheses
Aqueous solution syntheses are mostly based on mixing two solutions with different reactants. It is shown that freezing one solution and melting it in another solution provides a new interesting strategy to mix chemicals and to significantly change the reaction kinetics and thermodynamics. For example, a precursor solution containing a certain concentration of AgNO3 was frozen and dropped into a reductive NaBH4 solution at about 0 °C. The ultra-slow release of reactants was successfully achieved. An ice-melting process can be used to synthesize atomically dispersed metals, including cobalt, nickel, copper, rhodium, ruthenium, palladium, silver, osmium, iridium, platinum, and gold, which can be easily extended to other solution syntheses (such as precipitation, hydrolysis, and displacement reactions) and provide a generalized method to redesign the interphase reaction kinetics and ion diffusion in wet chemistry.
Wei, Hehe,Huang, Kai,Zhang, Le,Ge, Binghui,Wang, Dong,Lang, Jialiang,Ma, Jingyuan,Wang, Da,Zhang, Shuai,Li, Qunyang,Zhang, Ruoyu,Hussain, Naveed,Lei, Ming,Liu, Li-Min,Wu, Hui
supporting information
p. 3354 - 3359
(2018/02/21)

Selective hydrogenolysis of Α–O–4, Β–O–4, 4–O–5 C–O bonds of lignin-model compounds and lignin-containing stillage derived from cellulosic bioethanol processing
Benzyl phenyl ether (BPE), phenethyl phenyl ether (PPE) and diphenyl ether (DPE) have been selected as model compounds of the most abundant and significant ether linkages found within the complex structure of lignin (e.g. α–O–4, β–O–4, and 4–O–5, respectively). The catalytic hydrogenolysis of these compounds has been carried out using several Ru, Pd and Ni catalysts supported over different metal oxides (e.g. Al2O3, ZrO2, TiO2) and carbon materials (e.g. active carbon, multiwall carbon nanotubes). The conversion of these compounds at relevant hydroprocessing conditions (150?°C, 25?bar-g in H2 atmosphere) is much dependent on the labile nature of the relevant ether bonds of the selected model compounds. Conversion levels for the three compounds increases in the following order: DPE (4–O–5 linkage)??Pd?>?Ru). The catalytic systems with easier reducible species performes better in the conversion of the dimer models. Besides, a preliminary study on the catalytic depolymerization of a real lignin stream (lignin-containing 2G bioethanol plants stillage) has been carried out. Detailed characterization by 13C-1H heteronuclear single-quantum correlation spectroscopy (HSQC) showed that on 5?wt.% Ru/C it is possible to achieve 50% desapearance of the most abundant lignin ether bond (i.e. β–O–4) and liquid yields above 50?wt.%.
Gómez-Monedero,Ruiz,Bimbela,Faria
p. 60 - 76
(2017/05/16)

Ru decorated with NiCoP: An efficient and durable hydrogen evolution reaction electrocatalyst in both acidic and alkaline conditions
The construction of a high efficiency and stable catalyst for use in electrochemical hydrogen generation has great significance for renewable energy technologies. Herein, we show for the first time that Ru decorated with NiCoP is an excellent hydrogen evolving catalyst in both acidic and alkaline conditions, close in performance to that of Pt/C.
Liu, Suli,Liu, Qinpu,Lv, Yun,Chen, Biyao,Zhou, Quan,Wang, Lei,Zheng, Qiuhui,Che, Chenjing,Chen, Changyun
supporting information
p. 13153 - 13156
(2017/12/26)

Discontinuously covered IrO2-RuO2@Ru electrocatalysts for the oxygen evolution reaction: How high activity and long-term durability can be simultaneously realized in the synergistic and hybrid nano-structure
Here, we present our effort in simultaneously enhancing the intrinsic activity and improving the durability of catalysts based on Ir and Ru oxides. Through successful design and fabrication of the discontinuously covered IrO2-RuO2@Ru (3:1) supported structure, we are able to combine the high activity of RuO2 and the outstanding stability of IrO2. Specifically, the overpotential of the IrO2-RuO2@Ru (3:1) catalyst at 10 mA cm-2 is only 281 mV, and the turnover frequency (TOF) values of IrO2-RuO2@Ru (3:1), Ir3RuO2 and IrO2 catalysts are ca. 0.039, 0.023 and 0.017 s-1 at 1.55 V, respectively, indicating that IrO2-RuO2@Ru (3:1) exhibits higher intrinsic activity and the active surface sites possess greater ability to generate oxygen. The excellent durability of the IrO2-RuO2@Ru (3:1) catalyst is confirmed with the overpotential at 10 mA cm-2 positively shifting by only 16 mV after 3000 cycles through accelerated durability tests. Remarkably, the IrO2-RuO2@Ru (3:1) catalyst exhibits a huge advantage in reducing the use of precious metals in water electrolysis. Hence, the supported iridium-ruthenium bimetallic oxides show huge potential towards an active and stable application for the oxygen evolution reaction in acidic media.
Li, Guoqiang,Li, Songtao,Ge, Junjie,Liu, Changpeng,Xing, Wei
supporting information
p. 17221 - 17229
(2017/09/01)

Synthesis, some properties, and crystalline modifications of fac-[Ru(NO)(Py)2Cl3]
According to the data of 1H NMR spectroscopy, trans-hydroxochloro complexes containing from two to four pyridine molecules in the internal sphere are formed on the heating of a dilute aqueous solution of K2[Ru(NO)Cl5] with pyridine. The evaporation of the reaction solution with concentrated hydrochloric acid gives fac-[Ru(NO)(Py)2Cl3] (I) in a yield of ~90%. The structures of two crystalline modifications of this complex are determined by X-ray diffraction analysis (CIF files ССDС nos. 1452208 (Ia) and 1452207 (Ib)). IR spectroscopy shows that the irradiation of complex I (λ ~ 450 nm, T = 80 K) results in photoisomerization with the formation of the metastable state MS1 in which the nitroso group is coordinated by the oxygen atom. The activation parameters of the photoisomerization are determined from the data of differential scanning calorimetry (DSC). Compound trans-[Ru(NO)Py4(OH)]Cl2 ? H2O is isolated in a yield of ~70% on reflux of complex I with a pyridine excess in an aqueous solution, and the presence of molecules of water of crystallization in this compound is confirmed by thermal gravimetry (TG) and IR spectroscopy.
Makhinya,Il’in,Yamaletdinov,Baidina,Tkachev,Zubareva,Korol’kov,Piryazev
p. 768 - 774
(2016/12/14)

Growth of highly conformal ruthenium-oxide thin films with enhanced nucleation by atomic layer deposition
Highly conformal and conductive RuO2 thin films were deposited without nucleation delay using atomic layer deposition (ALD) by zero-valent metallorganic precursor, (ethylbenzyl)(1,3-cyclohexadienyl)Ru(0) (EBCHDRu, C14H18Ru) and molecular oxygen (O2) as a precursor and reactant, respectively. RuO2 thin films could be successfully prepared by controlling the process parameters, such as a reactant flow rate, a reactant pulsing time, a precursor pulsing time, and a deposition temperature. X-ray diffractometry, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry analysis revealed that the formation of a RuO2 phase became favorable with increasing both the reactant flow rate and the pulsing time and with decreasing the precursor pulsing time and the deposition temperature. With the optimized pulsing conditions, the RuO 2 film deposited at 225 °C had a tetragonal structure and exhibited excellent properties such as the low resistivity of 118 μΩ-cm, the high density of 6.85 g/cm3 close to the bulk value, and the negligible roughness of 0.33 nm. The growth rate of ALD-RuO 2 was as high as 0.186 nm/cycle on the SiO2 substrate and the number of incubation cycles was negligible as 2. The film showed excellent step coverage of ～100% onto 25-nm-width trench structures with an aspect ratio of 4.5. The ALD-RuO2 was highly stable up to annealing at 700 °C in both O2 and N2 ambient. Finally, the ALD-RuO2 film was evaluated as a bottom electrode of a metal-insulator-metal capacitor with a high-k (dielectric constant) ALD-TiO 2 dielectric. The dielectric constant of ALD-TiO2 was confirmed to be as high as ～68. This extremely high dielectric constant was attributed to the formation of a rutile-structured TiO2 film on top of the ALD-RuO2 bottom electrode, as evidenced by high-resolution transmission electron microscopy analysis.
Park, Ji-Yoon,Yeo, Seungmin,Cheon, Taehoon,Kim, Soo-Hyun,Kim, Min-Kyu,Kim, Hyungjun,Hong, Tae Eun,Lee, Do-Joong
p. 529 - 539
(2014/06/23)

Synthesis and crystal structure of oxygen-deficient Bilayer Ruthenate Sr3Ru2O7-δ
The structural properties of oxygen-deficient Ruddlesden-Popper-type Sr3Ru2O7-δ compounds are presented. Sr3Ru2O7-δ compounds (δ≤0.17, 0.23, 0.28, 0.40, and 0.47) were obtained by hydrogen reduction of the parent Sr3Ru2O7 ruthenate. Rietveld structure refinements were performed to determine the crystal structure of the reduced compounds. Oxygen deficiency in the samples was studied by redox titrations and the Ru3+ content was confirmed by electron paramagnetic resonance. Magnetisation measurements were performed to study the magnetic response of the reduced phases. Removal of the oxygen atoms from the parent compound resulted in the decrease of the c-lattice parameter and increase of the a-lattice parameter that is related to partial reduction of Ru4+, in Sr3Ru2O7, to Ru3+. Rietveld analyses showed that the apical oxygen atoms of the RuO6 octahedra were partially lost during reduction. Redox titration experiments showed a linear correlation between reduction of the compounds and the annealing time under H2. CSIRO 2014.
Martinez-Anaya, Oliver,Garcia-Valdes, Jesus,De La Mora, Pablo,Tavizon, Gustavo
p. 777 - 783
(2014/06/09)

A series of NiM (M = Ru, Rh, and Pd) bimetallic catalysts for effective lignin hydrogenolysis in water
In this paper, NiRu, NiRh, and NiPd catalysts were synthesized and evaluated in the hydrogenolysis of lignin C-O bonds, which is proved to be superior over single-component catalysts. The optimized NiRu catalyst contains 85% Ni and 15% Ru, composed of Ni surface-enriched, Ru-Ni atomically mixed, ultrasmall nanoparticles. The Ni85Ru15 catalyst showed high activity under low temperature (100°C), low H2 pressure (1 bar) in β-O-4 type C-O bond hydrogenolysis. It also exhibited significantly higher activity over Ni and Ru catalysts in the direct conversion of lignin into monomeric aromatic chemicals. Mechanistic investigation indicates that the synergistic effect of NiRu can be attributed to three factors: (1) increased fraction of surface atoms (compared with Ni), (2) enhanced H2 and substrate activation (compared with Ni), and (3) inhibited benzene ring hydrogenation (compared with Ru). Similarly, NiRh and NiPd catalysts were more active and selective than their single-component counterparts in the hydrogenolysis of lignin model compounds and real lignin.
Zhang, Jiaguang,Teo, Jason,Chen, Xi,Asakura, Hiroyuki,Tanaka, Tsunehiro,Teramura, Kentaro,Yan, Ning
p. 1574 - 1583
(2014/05/20)

Temperature-dependent formation of Ru-based nanocomposites: Structures and properties
A new route to produce Ru-based nanocomposites with mixed valence states of ruthenium is reported in this paper via a solid-phase sintering process. Precursor particles were prepared by an intimate mixing of RuCl3 and native β-cyclodextrin (β-CD) with a molar ratio of 1:1, followed by a sintering process at various temperatures ranging from 573 to 1173 K in ambient atmosphere. The so-obtained composite nanomaterials have been characterized by X-ray diffraction and notably the results show that an adjustment of the temperature enabled us to obtain Ru-based nanoparticles with controllable compositions. The surface-enhanced Raman scattering performances of the obtained nanomaterials have been analyzed using Rhodamine 6G (R6G) as the Raman probe. Their magnetic behaviors have been investigated as a function of the field strengths. The present work provides a significant advance in the development of both transformation in valence states of transition metals and in situ nanocomposites of metal/metal oxide combinations. This journal is the Partner Organisations 2014.
Teng, Yue,Song, Le Xin,Ponchel, Anne,Monflier, Eric,Shao, Zhi Cheng,Xia, Juan,Yang, Zheng Kun
p. 26847 - 26854
(2014/07/21)

Fabrication of ruthenium metal nanosheets via topotactic metallization of exfoliated ruthenate nanosheets
The metallization behavior of molecularly thin RuO2 nanosheets obtained from complete delamination of layered ruthenates was studied. Interestingly, the RuO2 nanosheets in a monolayer state topotactically transformed into a single layer of Ru atoms, i.e., ruthenium metal nanosheets, which can be regarded as a new family of nanosized metals.
Fukuda, Katsutoshi,Sato, Jun,Saida, Takahiro,Sugimoto, Wataru,Ebina, Yasuo,Shibata, Tatsuo,Osada, Minoru,Sasaki, Takayoshi
p. 2280 - 2282
(2013/04/10)

Topochemical fluorination of Sr3(M0.5Ru 0.5)2O7 (M = Ti, Mn, Fe), n = 2, Ruddlesden-popper phases
Reaction of the appropriate Sr3(M0.5Ru 0.5)2O7 (M = Ti, Mn, Fe), n = 2, Ruddlesden-Popper oxide with CuF2 under flowing oxygen results in formation of the oxide-fluoride phases Sr3(Ti0.5Ru 0.5)2O7F2, Sr3(Mn 0.5Ru0.5)2O7F2, and Sr3(Fe0.5Ru0.5)2O 5.5F3.5 via a topochemical anion insertion/substitution process. Analysis indicates the titanium and manganese phases have Ti 4+, Ru6+ and Mn4+, Ru6+ oxidation state combinations, respectively, while Moessbauer spectra indicate an Fe3+, Ru5.5+ combination for the iron phase. Thus, it can be seen that the soft fluorination conditions employed lead to formation of highly oxidized Ru6+ centers in all three oxide-fluoride phases, while oxidation states of the other transition metal M cations remain unchanged. Fluorination of Sr3(Ti0.5Ru0.5) 2O7 to Sr3(Ti0.5Ru 0.5)2O7F2 leads to suppression of magnetic order as the fluorinated material approaches metallic behavior. In contrast, fluorination of Sr3(Mn0.5Ru0.5) 2O7 and Sr3(Fe0.5Ru 0.5)2O7 lifts the magnetic frustration present in the oxide phases, resulting in observation of long-range antiferromagnetic order at low temperature in Sr3(Mn0.5Ru 0.5)2O7F2 and Sr3(Fe 0.5Ru0.5)2O5.5F3.5. The influence of the topochemical fluorination on the magnetic behavior of the Sr3(M0.5Ru0.5)2OxF y phases is discussed on the basis of changes to the ruthenium oxidation state and structural distortions.
Romero, Fabio Denis,Bingham, Paul A.,Forder, Susan D.,Hayward, Michael A.
p. 3388 - 3398
(2013/05/08)

Influence of the operating conditions and kinetic analysis of the selective hydrogenation of oleic acid on Ru-Sn-B/Al2O3 catalysts
The influence of the operating conditions on the selectivity and activity of Ru-Sn-B/Al2O3 catalysts for the hydrogenation of oleic acid to oleyl alcohol was studied. It was found that the Ru-Sn-B/Al 2O3 catalyst is selective to oleyl alcohol while Ru or Ru-B/Al2O3 catalysts are not selective to produce oleyl alcohol. The electronic and catalytic properties of Ru are modified by the strong interaction between Sn and B. The incorporation of Sn leads to catalysts capable of producing oleyl alcohol. The experiments of oleic acid hydrogenation showed that an increase in reaction temperature leads to an increase in activity while the selectivity to oleyl alcohol goes through a maximum. This is because the reactions of hydrogenation of CC double bond have lower activation energies than hydrogenolytic reactions. The increase in operating pressure has a positive effect on conversion and a more important effect on selectivity. A very simple first order kinetic model is proposed and reasonably represents the results obtained. This model can be useful to compare catalyst performance more rationally.
Sánchez, María A.,Pouilloux, Yannick,Mazzieri, Vanina A.,Pieck, Carlos L.
p. 552 - 558
(2013/09/23)

Solvent effects in the hydrogenation of 2-butanone
In liquid-phase reaction systems, the role of the solvent is often limited to the simple requirement of dissolving and/or diluting substrates. However, the correct choice, either pure or mixed, can significantly influence both reaction rate and selectivity. For multi-phase heterogeneously catalysed reactions observed variations may be due to changes in mass transfer rates, reaction mechanism, reaction kinetics, adsorption properties and combinations thereof. The liquid-phase hydrogenation of 2-butanone to 2-butanol over a Ru/SiO 2 catalyst, for example, shows such complex rate behaviour when varying water/isopropyl alcohol (IPA) solvent ratios. In this paper, we outline a strategy which combines measured rate data with physical property measurements and molecular simulation in order to gain a more fundamental understanding of mixed solvent effects for this heterogeneously catalysed reaction. By combining these techniques, the observed complex behaviour of rate against water fraction is shown to be a combination of both mass transfer and chemical effects.
Akpa,D'Agostino,Gladden,Hindle,Manyar,McGregor,Li,Neurock,Sinha,Stitt,Weber,Zeitler,Rooney
p. 30 - 41
(2012/06/01)

Liquid phase hydrogenation of methyl-N-Boc-pyrrole-2-carboxylate over tailored Ru nanoparticles
Ru nanoparticles were prepared in ethylene glycol at different pH, temperature and RuCl3·nH2O concentration as well as with and without poly(N-vinyl-2-pyrrolidone) (PVP) as protective agent. They were characterized in the synthesis solution by small-angle X-ray scattering (SAXS) using Guinier analysis and indirect Fourier transformation (IFT) technique and by TEM, XRD, XPS and ATR-IR. From SAXS data evaluation, it was derived that size of the formed Ru nanoparticles depends mainly on the pH of the synthesis solution and only to a minor extent on Ru precursor concentration and reduction temperature. The impact of PVP on particle size was also only very low. The Ru nanoparticles were active for hydrogenation of methyl-N-Boc-pyrrole- 2-carboxylate in ethanol solution at 25 °C and p(H2) = 5 bar. Particle size was found to be an important parameter determining hydrogenation activity. A maximum in the activity (TOF = 1000 h-1) was obtained over Ru nanoparticles with a mean particle diameter of about 1.6 nm. However, differently prepared nanoparticles of nearly identical particle size diverge strongly in their catalytic activity. These differences might be due to different surface sites and a blocking of active metal surface sites by surface intermediates formed during nanoparticle formation. Both surface structure and the extent of such blocking strongly depend on the synthesis conditions. If the nanoparticles were protected by PVP, their hydrogenation activity clearly drops in comparison to similarly sized nanoparticles without PVP protection.
Steinfeldt, Norbert,Sebek, Michael,Jaehnisch, Klaus
p. 249 - 258
(2012/07/02)

The properties of Ru films deposited by remote plasma atomic layer deposition on Ar plasma-treated SiO2
By using remote plasma atomic layer deposition (ALD), ruthenium thin films were deposited on SiO2 using bis(ethylcyclopentadienyl)ruthenium [Ru(EtCp)2] as a Ru precursor and an ammonia plasma as a reactant. Different plasma treatments were applied, and the best results were obtained with the Ar plasma-treated SiO2 surface. The initial transition region usually observed with Ru deposition before continuous film formation was present, and the number of ALD cycles required to obtain a continuous film was reduced to about 35 cycles on the Ar plasma-treated SiO2 substrates. The transition region of Ru cluster growth on Ar plasma-treated SiO2 was investigated with transmission electron microscopy (TEM). Most of the Ru clusters were larger and better crystallized on the Ar plasma-treated SiO 2 than on untreated SiO2. Also, Ru films deposited on the treated SiO2 exhibited a (002) preferred orientated structure with a film resistivity of about 10.26 μω-cm. The growth rates of Ru after passing the transition region were similar on both the treated and untreated SiO2 at about 1.7 A/cycles. From the Auger electron spectroscopy (AES) spectrum, a very low content of oxygen was observed in the Ru films. About 9% carbon was detected by a rutherford backscattering spectrometer (RBS). Copyright
Park, Taeyong,Choi, Dongjin,Choi, Hagyoung,Jeon, Hyeongtag
p. 302 - 305
(2012/04/17)

Structural and electrical properties of ternary Ru-AlN thin films prepared by plasma-enhanced atomic layer deposition
Ruthenium-aluminum-nitride (Ru-AlN) thin films were grown by plasma-enhanced atomic layer deposition (PEALD) at 300 °C. The Ru intermixing ratio of Ru-AlN thin films was controlled by the number of Ru unit cycles, while the number of AlN unit cycles was fixed to one cycle. The electrical resistivity of Ru-AlN thin film decreased with increasing the Ru intermixing ratio, but a drastic decrease in electrical resistivity was observed when the Ru intermixing ratio was around 0.58-0.78. Bright-field scanning transmission electron microscope (BF-STEM) and energy-dispersive X-ray spectroscopy (EDX) element mapping analysis revealed that the electrical resistivity of Ru-AlN thin film was strongly dependent on the microstructures as well as on the Ru intermixing ratio. Although the electrical resistivity of Ru-AlN thin films decreased with increasing the Ru intermixing ratio, a drastic decrease in electrical resistivity occurred where the electrical paths formed as a result of the coalescence of Ru nanocrystals.
Shin, Yu-Ri,Kwack, Won-Sub,Park, Yun Chang,Kim, Jin-Hyock,Shin, Seung-Yong,Moon, Kyoung Il,Lee, Hyung-Woo,Kwon, Se-Hun
p. 790 - 793
(2012/05/20)

Ru cyclooctatetraene precursors for MOCVD
A series of Ru0 cyclooctatetraene complexes are presented with optimal properties for MOCVD (metal organic chemical vapour deposition) applications, including combinations of the two lowest melting points and lowest decomposition temperatures yet reported for such materials. The compounds are easy to handle and lead to highly conformal thin films of Ru on SiO2 features; even within holes with aspect ratios of 40:1. SEM, AFM and XPS studies confirm the near ideal nature of the resulting conformal thin film.
Ando, Tatsuya,Nakata, Naoki,Suzuki, Kazuharu,Matsumoto, Takahiro,Ogo, Seiji
p. 1678 - 1682
(2012/03/22)

Nitrene-functionalized ruthenium nanoparticles
Ruthenium nanoparticles protected by ruthenium-nitrene π bonds were prepared by refluxing bare ruthenium colloids (2.12 ± 0.72 nm in diameter) and 4-dodecylbenezenesulfonyl azide in sec-butylbenzene. Thermogravimetric analysis (TGA) of the resulting nanoparticles showed that on average there were about 84.1 ligands on the nanoparticle surface. XPS studies showed a 1:1 atomic ratio between nitrogen and sulfur, consistent with the formation of nitrene fragments by the thermal decomposition of the azide precursors. In addition, the binding energies of Ru3d and N1s electrons suggested a covalent nature of the RuN interfacial linkage which appeared in FTIR measurements with a vibrational band at 1246 cm-1. Because of such conjugated bonding interactions, extensive intraparticle charge delocalization occurred, and the nanoparticle-bound nitrene moieties behaved analogously to azo derivatives, as manifested in UV-vis and fluorescence measurements. Further testimony of the formation of RuN interfacial linkages was highlighted in the unique reactivity of the nanoparticles with alkenes by imido transfer, which was evidenced in spectroscopic and electrochemical studies. The Royal Society of Chemistry.
Kang, Xiongwu,Song, Yang,Chen, Shaowei
p. 19250 - 19257
(2012/11/07)

Photocatalytic hydrogen evolution under highly basic conditions by using Ru nanoparticles and 2-phenyl-4-(1-naphthyl)quinolinium ion
Photocatalytic hydrogen evolution with a ruthenium metal catalyst under basic conditions (pH 10) has been made possible for the first time by using 2-phenyl-4-(1-naphthyl)quinolinium ion (QuPh+-NA), dihydronicotinamide adenine dinucleotide (NADH), and Ru nanoparticles (RuNPs) as the photocatalyst, electron donor, and hydrogen-evolution catalyst, respectively. The catalytic reactivity of RuNPs was virtually the same as that of commercially available PtNPs. Nanosecond laser flash photolysis measurements were performed to examine the photodynamics of QuPh+-NA in the presence of NADH. Upon photoexcitation of QuPh+-NA, the electron-transfer state of QuPh+-NA (QuPh?-NA ?+) is produced, followed by formation of the π-dimer radical cation with QuPh+-NA, [(QuPh?-NA?+) (QuPh+-NA)]. Electron transfer from NADH to the π-dimer radical cation leads to the production of 2 equiv of QuPh?-NA via deprotonation of NADH?+ and subsequent electron transfer from NAD? to QuPh+-NA. Electron transfer from the photogenerated QuPh?-NA to RuNPs results in hydrogen evolution even under basic conditions. The rate of electron transfer from QuPh ?-NA to RuNPs is much higher than the rate of hydrogen evolution. The effect of the size of the RuNPs on the catalytic reactivity for hydrogen evolution was also examined by using size-controlled RuNPs. RuNPs with a size of 4.1 nm exhibited the highest hydrogen-evolution rate normalized by the weight of RuNPs.
Yamada, Yusuke,Miyahigashi, Takamitsu,Kotani, Hiroaki,Ohkubo, Kei,Fukuzumi, Shunichi
p. 16136 - 16145
(2011/11/11)

Aqueous-phase hydrodeoxygenation of carboxylic acids to alcohols or alkanes over supported Ru catalysts
For the aqueous-phase hydrodeoxygenation (APHDO) of carboxylic acids over the Ru/C, Ru/ZrO2 and Ru/Al2O3 catalysts, the CO hydrogenation and C-C bond cleavage reactions were studied by collecting reaction kinetics data and
Chen, Lungang,Zhu, Yulei,Zheng, Hongyan,Zhang, Chenghua,Zhang, Bin,Li, Yongwang
p. 217 - 227
(2012/02/02)

Influence of amines on the size control of in situ synthesized ruthenium nanoparticles in imidazolium ionic liquids
Very stable suspensions of small sized (c.a. 1.2 nm) and homogeneously dispersed ruthenium nanoparticles (RuNPs) were obtained by decomposition, under H2, of (η4-1,5-cyclooctadiene)(η6-1,3, 5-cyclooctatriene)ruthenium(0), [Ru(COD)(COT)], in various imidazolium derived ionic liquids (ILs: [RMIm][NTf2] (R = CnH2n+1 where n = 2; 4; 6; 8; 10) and in the presence of amines as ligands (1-octylamine, 1-hexadecylamine). These nanoparticles were compared to others stabilized either in pure ILs or by the same ligands in THF. NMR experiments (13C solution and DOSY) demonstrate that the amines are coordinated to the surface of the RuNPs. These RuNPs were investigated for the hydrogenation of aromatics and have shown a high level of recyclability (up to 10 cycles) with neither loss of activity nor significant agglomeration.
Salas, Gorka,Santini, Catherine C.,Philippot, Karine,Colliere, Vincent,Chaudret, Bruno,Fenet, Bernard,Fazzini, Pier Francesco
p. 4660 - 4668
(2011/06/23)

Effective octadecylamine system for nanocrystal synthesis
New chemical reactions and synthetic systems are of key importance for materials fabrication. In this work, we reported a facile and effective octadecylamine (ODA) synthetic system for various nanocrystals including metals, mixed metal oxides, metal/metal
Wang, Dingsheng,Li, Yadong
p. 5196 - 5202
(2011/08/08)

Electrodeposition of Pt-Ru nanoparticles on multi-walled carbon nanotubes: Application in sensitive voltammetric determination of methyldopa
A modified glassy carbon electrode, prepared by potentiostatic electrodeposition of platinum-ruthenium nanoparticles (Pt-RuNPs) onto a multi-walled carbon nanotube (MWCNT) layer, offers dramatic improvements in the stability and sensitivity of voltammetric responses toward methyldopa (m-dopa) compared to glassy carbon electrodes individually coated with MWCNT or Pt-RuNPs. The surface morphology and nature of the hybrid film (Pt-RuNPs/MWCNT) deposited on glassy carbon electrodes was characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. A remarkable enhancement in the microscopic area of the electrode together with the catalytic role of the composite modifier resulted in a considerable increase in the peak current (110 times) and a negative shift (-200 mV) in the oxidation peak potential of m-dopa. The mechanism of the electrocatalytic process on the surface of the modified electrode was analyzed via cyclic voltammograms at various potential sweep rates and pHs of the buffer solutions. Differential pulse voltammetry was applied and shown to provide a very sensitive analytical method for the determination of sub-micromolar amounts of m-dopa, for which a linear dynamic range of 0.05-40 μM and a detection limit of 10 nM was obtained. The modified electrode was successfully used for accurate determination of trace amounts of m-dopa in pharmaceutical and clinical preparations.
Shahrokhian, Saeed,Rastgar, Shokoufeh
p. 125 - 133
(2012/01/31)

Thermal analysis of cis-(dithiocyanato)(1,10-phenanthroline-5,6-dione)(4, 4′-dicarboxy-2,2′-bipyridyl)ruthenium(II) photosensitizer
Thermal behavior of [cis-(dithiocyanato)(1,10-phenanthroline-5,6-dione)(4, 4′-dicarboxy-2,2′-bipyridyl)ruthenium(II)], cis-[Ru(L1)(L2)(NCS) 2] (where the ligands were L1 = 1,10-Phenanthroline-5,6-dione, L2 = 4,4′-dicarboxy-2,2′-bipyridyl) was investigated by DTA/TG/DTG measurements under inert atmosphere in the temperature range of 298-1473 K as well as by XRD analysis of the final product. After making detailed analysis and comparison of thermogravimetrical and MSmeasurements of ruthenium complex, the decomposition mechanism of that complex was suggested. The values of activation energy and reaction orde r of the thermal decompositions were calculated by Ozawa Non-isothermal Method for all decomposition stages. The calculated activation energies vary in between 32 and 49 kJ mol-1.
Ocakoglu, Kasim,Emen, Fatih M.
p. 1017 - 1022
(2011/09/13)

On the oxidation of EuFe4Sb12 and EuRu 4Sb12
Rare-earth-filled transition-metal pnictides having the skutterudite-type structure have been proposed for use as high-temperature thermoelectric materials to recover waste heat from vehicle exhaust, among other applications. A previous investigation by this research group of one of the most studied skutterudites, CeFe4Sb12, found that, when exposed to air, this material oxidized at temperatures that are considerably below the proposed maximum operating temperature. Here, by the combined use of TGA, powder XRD, and XANES, it has been found that the substitution of Ce3+ and Fe2+ for larger rare-earth and transition-metal elements (Eu 2+ and Ru2+) results in a significantly higher oxidation temperature compared to that of CeFe4Sb12. This increase can be related to the increased orbital overlap provided by these larger atoms (Eu2+ and Ru2+ vs Ce3+ and Fe2+), enabling the development of stronger bonds. These results show how selective substitution of the constituent elements can significantly improve the thermal stability of materials.
Peddle, Jessica M.,Gaultois, Michael W.,Grosvenor, Andrew P.
p. 6263 - 6268
(2011/09/20)

Thermal decomposition of new ruthenium(II) complexes containing N-alkylphenothiazines
Thermal decomposition of chlorpromazine hydrochloride (CP?HCl), trifluoperazine dihydrochloride (TF?2HCl) and thioridazine hydrochloride (TR?HCl), and the ruthenium complexes with dimethyl sulfoxide (dmso) of composition [RuCl2(dmso)4] and L[RuCl3(dmso) 3]?xEtOH, L = CP?HCl, TF?2HCl orTR?HCl is described. The phenothiazines are stable to temperature range of 200-280 °C with an increasing stability order of TF?2H Cl 3(dmso)3]Cl?EtOH. The compound crystallizes with one EtOH, evaporating in part at room temperature.
Sovilj, Sofija P.,Pokol, Gyoergy,Szecsenyi, Katalin Meszaros,Hollo, Berta,Krstic, Milena
p. 27 - 32
(2011/10/11)

One-step synthesis of metallic and metal oxide nanoparticles using amino-PEG oligomers as multi-purpose ligands: Size and shape control, and quasi-universal solvent dispersibility
A one-step and room temperature synthesis toward metallic and metal oxide nanoparticles soluble both in water and organic solvent is reported. This was achieved using amino-PEG oligomers that make it possible to control the size and shape of the nanoparticles.
Rubio-Garcia, Javier,Coppel, Yannick,Lecante, Pierre,Mingotaud, Christophe,Chaudret, Bruno,Gauffre, Fabienne,Kahn, Myrtil L.
p. 988 - 990
(2011/02/23)

Optimization of Pt-Ir on carbon fiber paper for the electro-oxidation of ammonia in alkaline media
Plating bath concentrations of Pt(IV) and Ir(III) have been optimized as well as the total catalytic loading of bimetallic Pt-Ir alloy for the electro-oxidation of ammonia in alkaline media at standard conditions. This was accomplished using cyclic voltam
Boggs, Bryan K.,Botte, Gerardine G.
p. 5287 - 5293
(2011/01/06)

Olefin hydrogenation by ruthenium nanoparticles in ionic liquid media: Does size matter?
Tailor-made and size-controlled ruthenium nanoparticles, RuNPs, of three distinct sizes between 1 and 3 nm are generated from the decomposition of (η4-1,5-cyclooctadiene)(η6-1,3,5-cyclooctatriene) ruthenium(0) [Ru(COD)(COT)], under H2 in 1-butyl-3-methylimidazolium bis(trifluoromethanesulphonyl)imide, C1C4ImNTf 2, by simply varying experimental conditions. Catalytic hydrogenation of 1,3-cyclohexadiene, CYD, and cyclohexene, CYE, in C1C 4ImNTf2, has been used as a probe for the relationship between size and catalytic performance (activity and selectivity) of RuNPs. To allow comparison between different reactions, all catalytic reaction mixtures were diligently prepared in order that the parameters such as substrate/catalyst and substrate/ionic liquid ratio, and therefore, viscosity and mass transport factors remained constant. It was found that the catalytic activity increases with the NP size, while high selectivity is only observed with the smaller NPs. In addition, the studied RuNPs exhibit a high level of recyclability with neither loss of activity nor significant agglomeration.
Campbell, Paul S.,Santini, Catherine C.,Bayard, Franois,Chauvin, Yves,Collire, Vincent,Podgorsek, Ajda,Costa Gomes, Margarida F.,Sa, Jacinto
p. 99 - 107
(2011/02/25)

Selective-area atomic layer deposition using poly(vinyl pyrrolidone) as a passivation layer
Selective-area atomic layer deposition (ALD) was studied using poly(vinyl pyrrolidone) (PVP) films as growth-preventing mask layers. The PVP films were prepared by spin coating and patterned by UV lithography. The PVP films were tested in several ALD processes: iridium, platinum, ruthenium, Al 2O3, and ZrO2. The deposition temperatures were 250-300°C. In general, the PVP film passivated the surface against the noble metal processes, but the oxide films grew on PVP. However, the oxide films did not grow through the PVP film on the substrate surface and, therefore, the films could still be patterned, though with more of a lift-off method rather than with pure selective-area ALD.
Faerm, Elina,Kemell, Marianna,Santala, Eero,Ritala, Mikko,Leskelae, Markku
p. K10-K14
(2010/06/12)

Core-shell structured microcapsular-like Ru@SiO2 reactor for efficient generation of COx-free hydrogen through ammonia decomposition
The core-shell structured microcapsular-like Ru@SiO2 reactor is proved to be the most efficient material known to date for COx-free hydrogen production via ammonia decomposition for fuel cells application. The very active Ru core par
Li, Yanxing,Yao, Lianghong,Song, Yanyan,Liu, Shunqiang,Zhao, Jing,Ji, Weijie,Au, Chak-Tong
p. 5298 - 5300
(2010/08/20)

High temperature atomic layer deposition of ruthenium from N,N -dimethyl-1-ruthenocenylethylamine
Ruthenium thin films were grown by atomic layer deposition from N,N -dimethyl-1-ruthenocenylethylamine precursor. The growth was examined in the substrate temperature range of 325-500°C. The growth rate increased with the substrate temperature but was quite stable between 400 and 450°C. The films typically consisted of polycrystalline hexagonal ruthenium metal with a resistivity in the range of 10-20 μ cm when the film thickness was 10 nm and above. A resistivity of 49 μ cm could be achieved in the film as thin as 4 nm. Measurements on Al/Al2O3/Ru metal-insulator-metal (MIM) capacitors with Ru films as metal electrodes revealed a capacitive voltage behavior typical of MIM structures and appreciably high breakdown voltages.
Kukli, Kaupo,Ritala, Mikko,Kemell, Marianna,Leskelae, Markku
p. D35-D40
(2010/06/18)

Electrodeposition of arrays of Ru, Pt, and PtRu alloy 1D metallic nanostructures
Arrays of Ru, Pt, and PtRu one dimensional (1D) nanowires (NWs) and nanotubes (NTs) were prepared by electrodeposition through the porous structure of an anodic aluminum oxide (AAO) membrane. In each case, micrometer-long NW and NT were formed with an out
Ponrouch, Alexandre,Garbarino, Sbastien,Pronovost, Stphanie,Taberna, Pierre-Louis,Simon, Patrice,Guay, Daniel
p. K59-K65
(2011/01/09)

PtRu alloy nanostructure electrodes for methanol electrooxidation
In this work, PtRu nanostructure electrodes for methanol electrooxidation were electrodeposited by modulating an electrode potential. The PtRu nanostructures were characterized by scanning electron microscopy, transmission electron microscopy and X-ray di
Song, You-Jung,Han, Sang-Beom,Lee, Jong-Min,Park, Kyung-Won
p. 516 - 520
(2009/09/08)

Microwave irradiation assisted rapid synthesis of Fe-Ru bimetallic nanoparticles and their catalytic properties in water-gas shift reaction
Fe-Ru bimetallic nanoparticles were prepared by a microwave irradiation assisted glycol reduction method using poly-N-vinyl-2-pyrrolidone (PVP) as protective agent. The structure and morphology of the nanoparticles were characterized by X-ray diffraction
Du, Jian-Quan,Zhang, Yong,Tian, Tian,Yan, Shan-Cheng,Wang, Hai-Tao
p. 1347 - 1351
(2009/06/17)

Catalytically active nanoparticles stabilized by host-guest inclusion complexes in water
Hydrogenation of arene derivatives can be successfully performed in water by using ruthenium(0) nanoparticles stabilized by 1: 1 inclusion complexes formed between methylated cyclodextrins and an ammonium salt bearing a long alkyl chain. The Royal Society of Chemistry.
Hubert, Claudie,Denicourt-Nowicki, Audrey,Roucoux, Alain,Landy, David,Leger, Bastien,Crowyn, Gregory,Monflier, Eric
p. 1228 - 1230
(2009/07/10)