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Enhancing performance and stability of Sm_(0.2)Ce_(0.8)O_(1.9)-decorated La0.6Sr0.4CoO3−δ composite cathode in flat-tube solid oxide fuel cell 被引量:1
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作者 Zixiang Pei Jie Zhang +5 位作者 Yang Zhang Lizeng Han Tiancheng Fan Yang Wu Jianxin Wang Wanbing Guan 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2676-2688,共13页
The commercialization of solid oxide fuel cells depends on the cathode,which possesses both high catalytic activity and a thermal-expansion coefficient(TEC)that aligns with the electrolyte.Although the cobalt-based ca... The commercialization of solid oxide fuel cells depends on the cathode,which possesses both high catalytic activity and a thermal-expansion coefficient(TEC)that aligns with the electrolyte.Although the cobalt-based cathode La_(0.6)Sr_(0.4)CoO_(3)(LSC)offers excellent catalytic performance,its TEC is significantly larger than that of the electrolyte.In this study,we mechanically mix Sm_(0.2)Ce_(0.8)O_(2−δ)(SDC)with LSC to create a composite cathode.By incorporating 50wt%SDC,the TEC decreases significantly from 18.29×10^(−6) to 13.90×10^(−6) K^(−1).Under thermal-shock conditions ranging from room temperature to 800℃,the growth rate of polarization resistance is only 0.658%per cycle,i.e.,merely 49%that of pure LSC.The button cell comprising the LSC-SDC composite cathode operates stably for over 900 h without Sr segregation,with a voltage growth rate of 1.11%/kh.A commercial flat-tube cell(active area:70 cm^(2))compris-ing the LSC-SDC composite cathode delivers 54.8 W at 750℃.The distribution of relaxation-time shows that the non-electrode portion is the main rate-limiting step.This study demonstrates that the LSC-SDC mixture strategy effectively improves the compatibility with the electrolyte while maintaining a high output,thus rendering it a promising commercial cathode material. 展开更多
关键词 solid oxide fuel cell composite cathode lanthanum strontium cobalt oxide samarium-doped cerium oxide thermal expan-sion flat tube
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Catalytic performance of cobalt oxide-supported gold-palladium nanocatalysts for the removal of toluene and o-xylene 被引量:8
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作者 王治伟 刘雨溪 +3 位作者 杨涛 邓积光 谢少华 戴洪兴 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期207-216,共10页
Using the molten salt and polyvinyl alcohol-protected reduction method,we fabricated Co3O4 octahedron-supported Au-Pd(x(AuPdy)/Co3O4;x =(0.18,0.47,and 0.96) wt%;y(Pd/Au molar ratio) =1.85-1.97) nanocatalysts.T... Using the molten salt and polyvinyl alcohol-protected reduction method,we fabricated Co3O4 octahedron-supported Au-Pd(x(AuPdy)/Co3O4;x =(0.18,0.47,and 0.96) wt%;y(Pd/Au molar ratio) =1.85-1.97) nanocatalysts.The molten salt-derived Co3O4 sample possessed well-defined octahedral morphology,with an edge length of 300 nm.The Au-Pd nanoparticles,with sizes of 2.7-3.2 nm,were uniformly dispersed on the surface of Co3O4.The 0.96(AuPd1.92)/Co3O4 sample showed the highest catalytic activity for toluene and o-xylene oxidation,and the temperature required for achieving 90%conversion of toluene and o-xylene was 180 and 187 ℃,respectively,at a space velocity of 40000 mL/(g·h).The high catalytic performance of Co3O4 octahedron-supported Au-Pd nanocatalysts was associated with the interaction between Au-Pd nanoparticles and Co3O4 and high concentration of adsorbed oxygen species. 展开更多
关键词 Molten salt Cobalt oxide Au-Pd nanoparticle Volatile organic compound Catalytic oxidation
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Synthesis and characterization of porous cobalt oxide/copper oxide nanoplate as novel electrode material for supercapacitors 被引量:2
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作者 张水蓉 胡志彪 +3 位作者 刘开宇 刘艳珍 何方 谢清亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4054-4062,共9页
A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvi... A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvinylpyrrolidone(PVP) on the morphology and electrochemical performance of the composite were investigated. Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and nitrogen adsorption-desorption experiment were employed to characterize the microstructures and morphologies of the composite. Meanwhile, the electrochemical performances of the samples were studied using cyclic voltammetry(CV), galvanostatic charge-discharge test and electrochemical impedance spectroscopy(EIS). The results show that the porous Co3O4/Cu O-CTAB nanoplates own the best performance and exhibits a high specific capacitance of 398 F/g at 1 A/g with almost 100% capacitance retention over 2000 cycles, and it retains 90% of capacitance at 10 A/g. 展开更多
关键词 cobalt oxide/copper oxide composite hexadecyltrimethylammonium bromide(CTAB) polyvinylpyrrolidone(PVP) hydrothermal method SUPERCAPACITORS
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Chemoselective hydrogenation of phenol to cyclohexanol using heterogenized cobalt oxide catalysts 被引量:7
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作者 Zhongzhe Wei Yi Li +2 位作者 Jing Wang Haoran Li Yong Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第6期815-818,共4页
Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work,cobalt oxide nanoparticles(NPs) supported on porous carbon(Co Ox@CN) were fabricated by one-pot method and the h... Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work,cobalt oxide nanoparticles(NPs) supported on porous carbon(Co Ox@CN) were fabricated by one-pot method and the hybrids could efficiently and selectively hydrogenate phenol to cyclohexanol with a high yield of 98%. The high catalytic performance of Co Ox@CN was associate with the high surface area(340 m2/g) and uniformly dispersed NPs. Furthurmore, by detailed analysing the relationship between catalytic activity and catalysts composition, it clearly indicated that the Co3O4 in Co Ox@CN played an important role for the adsorption and activation of phenol and the in situ gernerated Co was responsible for hydrogen adsorption and dissociation. These findings provide a fundamental insight into the real active sites in hydrogenation of phenol using Co-based catalysts. 展开更多
关键词 PHENOL CYCLOHEXANOL Selective hydrogenation Cobalt oxides Metallic cobalt
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Preparation and catalytic behavior of reduced graphene oxide supported cobalt oxide hybrid nanocatalysts for CO oxidation 被引量:5
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作者 Yan WANG Ze-hua CHEN +6 位作者 Jing HUANG Gao-jie LI Jian-liang CAO Bo ZHANG Xing-ying CHEN Huo-li ZHANG Lei JIA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第11期2266-2274,共9页
The reduced graphene oxide (rGO) supported cobalt oxide nanocatalysts were prepared by the conventional precipitationand hydrothermal method. The as-prepared rGO-Co3O4 was characterized by the XRD, Raman spectrum, S... The reduced graphene oxide (rGO) supported cobalt oxide nanocatalysts were prepared by the conventional precipitationand hydrothermal method. The as-prepared rGO-Co3O4 was characterized by the XRD, Raman spectrum, SEM, TEM, N2-sorption,UV-Vis, XPS and H2-TPR measurements. The results show that the spinel cobalt oxide nanoparticles are highly fragmented on therGO support and possess uniform particle size, and the as-prepared catalysts possess high specific surface area and narrow pore sizedistribution. The catalytic properties of the as-prepared rGO-Co3O4 catalysts for CO oxidation were evaluated through acontinuous-flow fixed-bed microreactor-gas chromatograph system. The catalyst with 30% (mass fraction) reduced graphene oxideexhibits the highest activity for CO complete oxidation at 100 ℃. 展开更多
关键词 reduced graphene oxide cobalt oxide CATALYST CO oxidation catalytic activity
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A core-shell copper oxides-cobalt oxides heterostructure nanowire arrays for nitrate reduction to ammonia with high yield rate 被引量:3
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作者 Hui Liu Jingsha Li +5 位作者 Feng Du Luyun Yang Shunyuan Huang Jingfeng Gao Changming Li Chunxian Guo 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1619-1629,共11页
Electrochemical nitrate reduction to ammonia(NRA) can realize the green synthesis of ammonia(NH3) at ambient conditions, and also remove nitrate contamination in water. However, the current catalysts for NRA still fac... Electrochemical nitrate reduction to ammonia(NRA) can realize the green synthesis of ammonia(NH3) at ambient conditions, and also remove nitrate contamination in water. However, the current catalysts for NRA still face relatively low NH3yield rate and poor stability. We present here a core-shell heterostructure comprising cobalt oxide anchored on copper oxide nanowire arrays(CuO NWAs@Co_(3)O_(4)) for efficient NRA. The CuO NWAs@Co_(3)O_(4)demonstrates significantly enhanced NRA performance in alkaline media in comparison with plain CuO NWAs and Co_(3)O_(4)flocs. Especially, at-0.23 V vs. RHE, NH_(3) yield rate of the CuO NWAs@Co_(3)O_(4)reaches 1.915 mmol h^(-1)cm^(-2),much higher than those of CuO NWAs(1.472 mmol h^(-1)cm^(-2)), Co_(3)O_(4)flocs(1.222 mmol h^(-1)cm^(-2)) and recent reported Cu-based catalysts.It is proposed that the synergetic effects of the heterostructure combing atom hydrogen adsorption and nitrate reduction lead to the enhanced NRA performance. 展开更多
关键词 Electrocatalytic nitrate reduction Ammonia production Core–shell heterostructure Copper oxides nanowire arrays Cobalt oxidesflocs
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Revealing the correlation between structure evolution and electrochemical performance of high-voltage lithium cobalt oxide 被引量:3
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作者 Jiajia Wan Jianping Zhu +8 位作者 Yuxuan Xiang Guiming Zhong Xiangsi Liu Yixiao Li Kelvin H.L.Zhang Chaoyu Hong Jianming Zheng Kai Wang Yong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期786-794,共9页
Lithium cobalt oxide(LCO)is the dominating cathode materials for lithium-ion batteries(LIBs)deployed in consumer electronic devices for its superior volumetric energy density and electrochemical performances.The const... Lithium cobalt oxide(LCO)is the dominating cathode materials for lithium-ion batteries(LIBs)deployed in consumer electronic devices for its superior volumetric energy density and electrochemical performances.The constantly increasing demands of higher energy density urge to develop high-voltage LCO via a variety of strategies.However,the corresponding modification mechanism,especially the influence of the long-and short-range structural transitions at high-voltage on electrochemical performance,is still not well understood and needs further exploration.Based on ss-NMR,in-situ X-ray diffraction,and electrochemical performance results,it is revealed that the H3 to H1-3 phase transition dictates the structural reversibility and stability of LCO,thereby determining the electrochemical performance.The introduction of La and Al ions could postpone the appearance of H1-3 phase and induce various types of local environments to alleviate the volume variation at the atomic level,leading to better reversibility of the H1-3 phase and smaller lattice strain,and significantly improved cycle performance.Such a comprehensive long-range,local,and electronic structure characterization enables an in-depth understanding of the structural evolution of LCO,providing a guiding principle for developing high-voltage LCO for high energy density LIBs. 展开更多
关键词 Lithium cobalt oxide HIGH-VOLTAGE In-situ XRD Solid-state NMR Structure change
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Surface-mediated iron on porous cobalt oxide with high energy state for efficient water oxidation electrocatalysis 被引量:3
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作者 Jingsha Li Tao Hu +1 位作者 Changhong Wang Chunxian Guo 《Green Energy & Environment》 SCIE EI CSCD 2022年第4期662-671,共10页
Surface engineering of active materials to generate desired energy state is critical to fabricate high-performance heterogeneous catalysts.However, its realization in a controllable level remains challenging. Using ox... Surface engineering of active materials to generate desired energy state is critical to fabricate high-performance heterogeneous catalysts.However, its realization in a controllable level remains challenging. Using oxygen evolution reaction(OER) as a model reaction, we report a surface-mediated Fe deposition strategy to electronically tailor surface energy states of porous Co_(3)O_(4)(Fe-pCo_(3)O_(4)) for enhanced activity towards OER. The Fe-pCo_(3)O_(4) exhibits a low overpotential of 280 mV to reach an OER current density of 100 mA cm^(-2), and a fast-kinetic behavior with a low Tafel slop of 58.2 mV dec^(-1), outperforming Co_(3)O_(4)-based OER catalysts recently reported and also the noble IrO_(2). The engineered material retains 100% of its original activity after operating at an overpotential of 350 m V for 100 h. A combination of theoretical calculations and experimental results finds out that the surface doped Fe promotes a high energy state and desired coordination environment in the near surface region, which enables optimized OER intermediates binding and favorably changes the rate-determining step. 展开更多
关键词 Surficial Fe doping Cobalt oxides High energy state Water oxidation Oxygen evolution reactions
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Catalytic degradation of benzene over non-thermal plasma coupled Co-Ni binary metal oxide nanosheet catalysts 被引量:3
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作者 Zhi Jiang Dongxu Fang +3 位作者 Yuting Liang Yaoyu He Hisahiro Einaga Wenfeng Shangguan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第10期1-11,共11页
Non-thermal plasma(NTP)has been demonstrated as one of the promising technologies that can degrade volatile organic compounds(VOCs)under ambient condition.However,one of the key challenges of VOCs degradation in NTP i... Non-thermal plasma(NTP)has been demonstrated as one of the promising technologies that can degrade volatile organic compounds(VOCs)under ambient condition.However,one of the key challenges of VOCs degradation in NTP is its relatively low mineralization rate,which needs to be addressed by introducing catalysts.Therefore,the design and optimization of catalysts have become the focus of NTP coupling catalysis research.In thiswork,a series of two-dimensional nanosheet Co-Ni metal oxides were synthesized by microwave method and investigated for the catalytic oxidation of benzene in an NTP-catalysis coupling system.Among them,Co_(2)Ni_(1)O_(x)achieves 60%carbon dioxide(CO_(2))selectivity(SCO_(2))when the benzene removal efficiency(REbenzene)reaches more than 99%,which is a significant enhancement compared with the CO_(2)selectivity obtained without any catalysts(38%)under the same input power.More intriguingly,this SCO_(2)is also significantly higher than that of single metal oxides,NiO or Co_(3)O_(4),which is only around 40%.Such improved performance of this binary metal oxide catalyst is uniquely attributed to the synergistic effects of Co and Ni in Co_(2)Ni_(1)O_(x)catalyst.The introduction of Co_(2)Ni_(1)O_(x)was found to promote the generation of acrolein significantly,one of the key intermediates found in NTP alone system reported previously,suggest the benzene ring open reaction is promoted.Compared with monometallic oxides NiO and Co_(3)O_(4),Co_(2)Ni_(1)O_(x)also shows higher active oxygen proportion,better oxygenmobility,and stronger low-temperature redox capability.The above factors result in the improved catalytic performance of Co_(2)Ni_(1)O_(x)in the NTP coupling removal of benzene. 展开更多
关键词 BENZENE Nonthermal plasma CATALYSIS Cobalt metal oxide Nickel oxide Binary metal oxide
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Effect of erbium substitution on thermoelectric properties of complex oxide Ca_3Co_2O_6 at high temperatures 被引量:2
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作者 陆冬青 陈刚 +2 位作者 裴健 杨曦 线恒泽 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期168-172,共5页
Polycrystalline particles of Ca3-xErxCo2O6 (x=0.0, 0.15, 0.3, 0.45 and 0.6) were synthesized using sol-gel method combined with Low Temperature Sintering procedure (LTS) to evaluate the effect of Er substitution o... Polycrystalline particles of Ca3-xErxCo2O6 (x=0.0, 0.15, 0.3, 0.45 and 0.6) were synthesized using sol-gel method combined with Low Temperature Sintering procedure (LTS) to evaluate the effect of Er substitution on the thermoelectric properties of Ca3Co2O6. The crystal structure and microstructure were investigated using X-ray diffraction, infrared spectroscopy and scanning electron microscope. The electrical conductivity and Seebeck coefficient of the complex oxides were measured from 300 to 1073 K. The results showed that all the sampies were p-type semiconductors. The electrical conductivity increased with the increase in temperature. Er substitutions at Ca site affected carrier concentrations and carder mobility, resulting an increase in Seebeck coefficient and decrease in electrical conductivity. The power factor of Ca2.85Er0.15Co2O6 reached 10.66 μw/mK^2 at 1073 K. 展开更多
关键词 Ca3Co2O6 thermoelectric properties rare earth substitution cobalt oxide rare earths
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Synthesis of Co-Ni oxide microflowers as a superior anode for hybrid supercapacitors with ultralong cycle life 被引量:2
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作者 Ling-Yang Liu Xu Zhang +4 位作者 Hong-Xia Li Bao Liu Jun-Wei Lang Ling-Bin Kong Xing-Bin Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期206-212,共7页
Li-ion hybrid capacitors(LIHCs),composing of a lithium-ion battery(LIB) type anode and a supercapacitor(SC) type cathode,gained worldwide popularity due to harmonious integrating the virtues of high energy densi... Li-ion hybrid capacitors(LIHCs),composing of a lithium-ion battery(LIB) type anode and a supercapacitor(SC) type cathode,gained worldwide popularity due to harmonious integrating the virtues of high energy density of LIBs with high power density of SCs.Herein,nanoflakes composed microflower-like Co-Ni oxide(CoNiO) was successfully synthesized by a simple co-precipitation method.The atomic ratio of as-synthesized CoNiO is determined to be 1:3 through XRD and XPS analytical method.As a typical battery-type material,CoNiO and capacitor-type activated polyanilinederived carbon(APDC) were used to assemble LIHCs as the anode and cathode materials,respectively.As a result,when an optimized mass ratio of CoNiO and APDC was 1:2,CoNiO//APDC LIHC could deliver a maximum energy density of 143 Wh kg^-1 at a working voltage of 1-4 V.It is worth mentioning that the LIHC also exhibits excellent cycle stability with the capacitance retention of -78.2%after 15,000 cycles at a current density of 0.5 A g^-1. 展开更多
关键词 Li-ion hybrid capacitor Energy storage device Co-precipitation method Cobalt nickel oxide APDC Long cycle life
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Biocompatibility and biotoxicity of in-situ synthesized carboxylated nanodiamond-cobalt oxide nanocomposite 被引量:1
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作者 L.Syam Sundar Naser A.Anjum +3 位作者 M.C.Ferro Eduarda Pereira Manoj K.Singh A.C.M.Sousa 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第8期879-888,共10页
A nanocomposite that incorporates cobalt oxide(Co3O4) and nanodiamond(ND) can present both high magnetism(Co3O4) and high hardness(ND). ND particles have potential applications in a variety of fields such as p... A nanocomposite that incorporates cobalt oxide(Co3O4) and nanodiamond(ND) can present both high magnetism(Co3O4) and high hardness(ND). ND particles have potential applications in a variety of fields such as protein immobilization, biosensors, therapeutic molecule delivery and bio-imaging. However,limited information is available in literature on the in-situ synthesis of biocompatible magnetic materials and also on their potential biotoxicity as a result of their entry into environmental compartments and subsequent interaction with biota. In this work, a new kind of bio-compatible magnetic material –carboxylated nanodiamond(c ND) and Co3O4 was synthesized to obtain the c ND-Co3O4 nanocomposite.The synthesis procedure involved in-situ and chemical reduction of cobalt chloride(CoCl(26)H2O) and sodium borohydrate(NaBH4). The synthesized cND-Co3O4 nanocomposite was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The cyto-genotoxicity of the synthesized nanocomposite material was studied by using onion(Allium cepa L.) as a test model with concentrations of 5, 10 and 20 μg/ml. The study was also extended to cND and Co3O4 materials for comparison purpose. Co3O4 and cND exhibited their contrasting effects on mitosis and other cyto-genotoxic indices studied herein. This work provided fundamental data on the synthesis and the bio-toxicity of the c ND-Co3O4 nanocomposite, which, in turn, can help to expand their multidisciplinary applications. 展开更多
关键词 NANODIAMOND Cobalt oxide NANODIAMOND NANOCOMPOSITE Bio-toxicity Allium cepa
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Mesoporous cobalt monoxide-supported platinum nanoparticles:Superior catalysts for the oxidative removal of benzene 被引量:1
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作者 Jun Yang Yutong Xue +4 位作者 Yuxi Liu Jiguang Deng Xiyun Jiang Huan Chen Hongxing Dai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第4期170-179,共10页
Mesoporous Co3 O4(meso-Co3 O4)-supported Pt(0.53 wt.%Pt/meso-Co304)was synthesized via the KIT-6-templating and polyvinyl alcohol(PVA)-assisted reduction routes.Mesoporous CoO(meso-CoO)was fabricated through in situ r... Mesoporous Co3 O4(meso-Co3 O4)-supported Pt(0.53 wt.%Pt/meso-Co304)was synthesized via the KIT-6-templating and polyvinyl alcohol(PVA)-assisted reduction routes.Mesoporous CoO(meso-CoO)was fabricated through in situ reduction of meso-Co304 with glycerol,and the 0.18-0.69 wt.%Pt/meso-CoO samples were generated by the PVA-assisted reduction method.Meso-Co3 O4 and meso-CoO were of cubic crystal structure and the Pt nanoparticles(NPs)with a uniform size of ca.2 nm were well distributed on the mesoCo3 O4 or meso-CoO surface.The 0.56 wt%Pt/meso-CoO(0.56 Pt/meso-CoO)sample performed the best in benzene combustion(T50%=156℃and T90%=186℃at a space velocity of 80,000 mL/(g h)).Introducing water vapor or C02 with a certain concentration led to partial deactivation of 0.56 Pt/meso-CoO and such a deactivation was reversible.We think that the superior catalytic activity of 0.56 Pt/meso-CoO was intimately related to its good oxygen activation and benzene adsorption ability. 展开更多
关键词 Mesoporous cobalt oxide Supported Pt catalyst Benzene combustion Oxygen activation Benzene adsorption
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Robust cobalt oxide catalysts for controllable hydrogenation of carboxylic acids to alcohols 被引量:1
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作者 Song Song Dong Wang +5 位作者 Lu Di Chuanming Wang Weili Dai Guangjun Wu Naijia Guan Landong Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期250-257,共8页
The selective catalytic hydrogenation of carboxylic acids is an important process for alcohol production,while efficient heterogeneous catalyst systems are still being explored.Here,we report the selective hydrogenati... The selective catalytic hydrogenation of carboxylic acids is an important process for alcohol production,while efficient heterogeneous catalyst systems are still being explored.Here,we report the selective hydrogenation of carboxylic acids using earth‐abundant cobalt oxides through a reaction‐controlled catalysis process.The further reaction of the alcohols is completely hindered by the presence of carboxylic acids in the reaction system.The partial reduction of cobalt oxides by hydrogen at designated temperatures can dramatically enhance the catalytic activity of pristine samples.A wide range of carboxylic acids with a variety of functional groups can be converted to the corresponding alcohols at a yield level applicable to large‐scale production.Cobalt monoxide was established as the preferred active phase for the selective hydrogenation of carboxylic acids. 展开更多
关键词 Selective hydrogenation Carboxylic acids ALCOHOLS Cobalt oxides Reaction‐controlled catalysis
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Simultaneous determination of seven impurities in high-purity cobalt oxide by ICP-AES after matrix separation using 1-nitroso-2-naphthol as a precipitant 被引量:1
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作者 王艳 周春山 +1 位作者 段青兵 陈萍 《Journal of Central South University of Technology》 2002年第2期100-103,共4页
A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nit... A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nitroso 2 naphthol. The matrix effect of cobalt on the absorptions of trace impurities, the effects of reaction time, pH value, dosage of precipitant on the formation of cobalt 1 nitroso 2 naphthol complex, the effects of hydrochloric acid on the stability of this complex and masking of elements were studied. Recoveries of the impurities in spiked sample are from 90% to 110% with a precision of 1.1% 5.0% RSD. The detection limits of the seven elements are in the range of 0.01 0.24μg/g. The method can be applied to the analysis of high purity cobalt metal, cobalt oxide and other cobalt compounds. 展开更多
关键词 trace impurity high purity cobalt oxide matrix separation inductively coupled plasma atomic emission spectrometry (ICP AES)
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Unraveling and optimizing the metal-metal oxide synergistic effect in a highly active Co_(x)(CoO)_(1–x)catalyst for CO_(2)hydrogenation
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作者 Kun Zhao Marco Calizzi +6 位作者 Emanuele Moioli Mo Li Alexandre Borsay Loris Lombardo Robin Mutschler Wen Luo Andreas Zuttel 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期241-250,I0009,共11页
The relation between catalytic reactivities and metal/metal oxide ratios,as well as the functions of the metal and the metal oxides were investigated in the CO_(2)hydrogenation reaction over highly active Co_x(CoO)_(1... The relation between catalytic reactivities and metal/metal oxide ratios,as well as the functions of the metal and the metal oxides were investigated in the CO_(2)hydrogenation reaction over highly active Co_x(CoO)_(1–x)catalysts in operando.The catalytic reactivity of the samples in the CO_(2)methanation improves with the increased Co O concentration.Strikingly,the sample with the highest concentration of CoO,i.e.,Co_(0.2)(CoO)_(0.8),shows activity at temperatures lower than 200°C where the other samples with less CoO are inactive.The origins of this improvement are the increased amount and moderate binding of adsorbed CO_(2)on CoO sites.The derivative adsorption species are found to be intermediates of the CH4 formation.The metallic Co functions as the electronically catalytic site which provides electrons for the hydrogenation steps.As a result,an abundant amount of CoO combined with Co is the optimal composition of the catalyst for achieving the highest reactivity for CO_(2)hydrogenation. 展开更多
关键词 Cobalt and cobalt oxide REACTIVITY CO_(2)hydrogenation Active site Adsorption Activation energy
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Catalytic methanation reaction over alumina supported cobalt oxide doped noble metal oxides for the purification of simulated natural gas
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作者 Wan Azelee Wan Abu Bakar Rusmidah Alil +2 位作者 Abdul Aziz Abdul Kadir Salmiah Jamal Mat Rosid Nurul Shafeeqa Mohammad 《燃料化学学报》 EI CAS CSCD 北大核心 2012年第7期822-830,共9页
A series of alumina supported cobalt oxide based catalysts doped with noble metals such as ruthenium and platinum were prepared by wet impregnation method.The variables studied were difference ratio and calcination te... A series of alumina supported cobalt oxide based catalysts doped with noble metals such as ruthenium and platinum were prepared by wet impregnation method.The variables studied were difference ratio and calcination temperatures.Pt/Co(10∶90)/Al2O3 catalyst calcined at 700 ℃ was found to be the best catalyst which able to convert 70.10% of CO2 into methane with 47% of CH4 formation at maximum temperature studied of 400 ℃.X-ray diffraction analysis showed that this catalyst possessed the active site Co3O4 in face-centered cubic and PtO2 in the orthorhombic phase with Al2O3 existed in the cubic phase.According to the FESEM micrographs,both fresh and spent Pt/Co(10∶90)/Al2O3 catalysts displayed small particle size with undefined shape.Nitrogen Adsorption analysis showed that 5.50% reduction of the total surface area for the spent Pt/Co(10∶90)/Al2O3 catalyst.Meanwhile,Energy Dispersive X-ray analysis(EDX) indicated that Co and Pt were reduced by 0.74% and 0.14% respectively on the spent Pt/Co(10∶90)/Al2O3catalyst.Characterization using FT-IR and TGA-DTA analysis revealed the existence of residual nitrate and hydroxyl compounds on the Pt/Co(10∶90)/Al2O3 catalyst. 展开更多
关键词 natural gas cobalt oxide noble metal catalyst methanation reaction
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Electrical properties of new oxides (Ca_(0.85-x)Y_xOH)_(1.16)CoO_2 synthesized by hydrothermal process
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作者 裴健 陈刚 +2 位作者 贾德昌 孙净雪 于耀光 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第6期600-603,共4页
Layered cobalt oxides (Ca0.85–xYxOH)1.16CoO2 (x=0, 0.05, 0.1) were prepared by hydrothermal process and were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrical con... Layered cobalt oxides (Ca0.85–xYxOH)1.16CoO2 (x=0, 0.05, 0.1) were prepared by hydrothermal process and were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrical conductivity and Seebeck coefficient were measured from 323 to 573 K. The XRD and SEM analysis showed that all samples were single phase with plate-like morphology. The substitution of trivalent Y for divalent Ca had a remarkable effect on the enhancement of electrical properties. The maximum PF value, 9.17×10–5 W/(m?K2), was obtained for (Ca0.75Y0.1OH)1.16CoO2 at 573 K, indicating that they are promising thermoelectric materials for middle-temperature usage. 展开更多
关键词 layered cobalt oxide hydrothermal synthesis substituting electrical property rare earths
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Fabrication of heteroatom-doped cobalt oxide yolk-shell microsphere using recycled solution from waste materials and their excellent electrochemical properties as an anode material for lithium-ion batteries
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作者 Yeong Beom Kim Chanho Kim +3 位作者 Seung-Hyun Kim Yun Chan Kang Dongju Lee Gi Dae Park 《Rare Metals》 SCIE EI CAS CSCD 2024年第10期4934-4947,共14页
Heteroatom-doped transition metal oxides have attracted great attention as advanced anode materials for lithium-ion batteries due to their high theoretical capacity and superior properties.However,the limited resource... Heteroatom-doped transition metal oxides have attracted great attention as advanced anode materials for lithium-ion batteries due to their high theoretical capacity and superior properties.However,the limited resource availability has led to a substantial rise in prices for valuable metals such as Ni and Co,posing a significant challenge for their application.To address this issue,recycling of these metals from waste materials have gained prominence,and particularly the recovery of Co has been mostly focused on its economic benefits.Herein,we introduced a novel recycling strategy for fabrication of heteroatomdoped CoO_(x)(comprising mainly Co_(3)O_(4)with a minor CoO phase)anode with a yolk–shell structure for lithium-ion batteries,by separating Co from cemented tungsten carbide waste.By employing a simple leaching process and subsequent spray pyrolysis,the yolk–shell structured microsphere comprising CoO_(x)was successfully synthesized.Moreover,the presence of other waste metals in the leachate facilitated multi-heteroatom doping during synthesis.Interestingly,the introduction of various dopants into CoO_(x)induced oxygen vacancy formation,thereby enhancing the electrochemical properties of the CoO_(x)anode.As a result,compared with the phase-pure(undoped)CoO_(x)yolk–shell,the heteroatom-doped CoO_(x)yolk–shell exhibited robust cycling stability(602 mAh·g^(-1)for 200 cycles at 1 A·g^(-1))and excellent rate capability(210 mAh·g^(-1)at 10 A·g^(-1)). 展开更多
关键词 Recycling Heteroatom doping Cobalt oxide Anode Lithium-ion batteries
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Homogenous metallic deposition regulated by abundant lithiophilic sites in nickel/cobalt oxides nanoneedle arrays for lithium metal batteries
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作者 Fenqiang Luo Dawei Xu +4 位作者 Yongchao Liao Minghao Chen Shuirong Li Dechao Wang Zhifeng Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期11-18,I0001,共9页
Although lithium(Li)metal delivers the highest theoretical capacity as a battery anode,its high reactivity can generate Li dendrites and"dead"Li during cycling,resulting in poor reversibility and low Li util... Although lithium(Li)metal delivers the highest theoretical capacity as a battery anode,its high reactivity can generate Li dendrites and"dead"Li during cycling,resulting in poor reversibility and low Li utilization.Inducing uniform Li plating/stripping is the core of solving these problems.Herein,we design a highly lithiophilic carbon film with an outer sheath of the nanoneedle arrays to induce homogeneous Li plating/stripping.The excellent conductivity and 3D framework of the carbon film not only offer fast charge transport across the entire electrode but also mitigate the volume change of Li metal during cycling.The abundant lithiophilic sites ensure stable Li plating/stripping,thereby inhibiting the Li dendritic growth and"dead"Li formation.The resulting composite anode allows for stable Li stripping/plating under 0.5 mA cm^(-2) with a capacity of 0.5 mA h cm^(-2) for 4000 h and 3 mA cm^(-2) with a capacity of3 mA h cm^(-2) for 1000 h.The Ex-SEM analysis reveals that lithiophilic property is different at the bottom,top,or channel in the structu re,which can regulate a bottom-up uniform Li deposition behavior.Full cells paired with LFP show a stable capacity of 155 mA h g^(-1) under a current density of 0.5C.The pouch cell can keep powering light-emitting diode even under 180°bending,suggesting its good flexibility and great practical applications. 展开更多
关键词 Nickel/cobalt oxides Nanoneedle arrays Lithiophilic sites Lithium metal batteries
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