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Synthesis and functionalization of carbon xerogels to be used as supports for fuel cell catalysts 被引量:1
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作者 Jos L. Figueiredo Manuel F. R. Pereira 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第2期195-201,共7页
The synthesis and properties of carbon xerogels are briefly described in this mini-review, emphasizing the methods used for tuning their surface chemistry and textural properties in order to design efficient electroca... The synthesis and properties of carbon xerogels are briefly described in this mini-review, emphasizing the methods used for tuning their surface chemistry and textural properties in order to design efficient electrocatalysts for fuel cells. In particular, the role played by the surface functional groups in determining the loading, dispersion, oxidation state and stability of the metal phases is addressed. 展开更多
关键词 carbon xerogels fuel cells ELECTROcatalystS surface chemistry catalyst supports
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Preparation and characterization of Pt-WO_3/C catalysts for direct ethanol fuel cells 被引量:1
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作者 WU Feng LIU Yanhong WU Chuan 《Rare Metals》 SCIE EI CAS CSCD 2010年第3期255-260,共6页
Three co-impregnation/chemical reduction methods in acidic solutions of pH 〈 1,including ethylene glycol (EG),NaBH4,and HCOOH,were compared for Pt-WO3/C catalysts.Pt-WO3/C catalysts containing 10 wt.% and 20 wt.% p... Three co-impregnation/chemical reduction methods in acidic solutions of pH 〈 1,including ethylene glycol (EG),NaBH4,and HCOOH,were compared for Pt-WO3/C catalysts.Pt-WO3/C catalysts containing 10 wt.% and 20 wt.% platinum per carbon were prepared by the three methods; their morphology and electrocatalytic activities were characterized.The 20 wt.% Pt-WO3/C catalyst prepared by the co-impregnation/EG method presented the optimal dispersion with an average particle size of 4.6 nm and subsequently the best electrocatalytic activity,and so,it was further characterized.Its anodic peak current density for ethanol oxidation from linear sweep voltammetry (LSV) is 7.9 mA·cm^-2,which is 1.4 and 5.2 times as high as those of the catalysts prepared by co-impregnation/NaBH4 and co-impregnation/ HCOOH reduction methods,2.1 times as high as that of the 10 wt.% Pt-WO3/C catalyst prepared by co-impregnation/EG method,respectively. 展开更多
关键词 direct ethanol fuel cells catalystS preparation method CHARACTERIZATION ethanol electrooxidation
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Pt/WO_3/C nanocomposite with parallel WO_3 nanorods as cathode catalyst for proton exchange membrane fuel cells 被引量:5
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作者 Meiling Dou Ming Hou +4 位作者 Zhilin Li Feng Wang Dong Liang Zhigang Shao Baolian Yi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第1期39-44,共6页
Pt/WO3/C nanocomposites with parallel WO3 nanorods were synthesized and applied as the cathode catalyst for proton exchange membrane fuel cells (PEMFCs). Electrochemical results and single cell tests show that an en... Pt/WO3/C nanocomposites with parallel WO3 nanorods were synthesized and applied as the cathode catalyst for proton exchange membrane fuel cells (PEMFCs). Electrochemical results and single cell tests show that an enhanced activity for the oxygen reduction reaction (ORR) is obtained for the Pt/WO3/C catalyst compared with Pt/C. The higher catalytic activity might be ascribed to the improved Pt dispersion with smaller particle sizes. The Pt/WO3/C catalyst also exhibits a good electrochemical stability under potential cycling. Thus, the Pt/WO3/C catalyst can be used as a potential PEMFC cathode catalyst. 展开更多
关键词 tungsten oxides Pt nanoparticles catalyst proton exchange membrane fuel cells
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Nano-Morphology of a Polymer Electrolyte Fuel Cell Catalyst Layer Imaging, Reconstruction and Analysis 被引量:5
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作者 Simon Thiele Roland Zengerle Christoph Ziegler 《Nano Research》 SCIE EI CAS CSCD 2011年第9期849-860,共12页
The oxygen reduction reaction (ORR) in the cathode catalyst layer (CCL) of polymer electrolyte fuel cells (PEFC) is one of the major causes of performance loss during operation. In addition, the CCL is the most ... The oxygen reduction reaction (ORR) in the cathode catalyst layer (CCL) of polymer electrolyte fuel cells (PEFC) is one of the major causes of performance loss during operation. In addition, the CCL is the most expensive component due to the use of a Pt catalyst. Apart from the ORR itself, the species transport to and from the reactive sites determines the performance of the PEFC. The effective transport properties of the species in the CCL depend on its nanostructure. Therefore a three-dimensional reconstruction of the CCL is required. A series of two-dimensional images was obtained from focused ion beam- scanning electron microscope (FIB-SEM) imaging and a segmentation method for the two-dimensional images has been developed. The pore size distribution (PSD) was calculated for the three-dimensional geometry. The influence of the alignment and the anisotropic pixel size on the PSD has been investigated. Pores were found in the range between 5 nm and 205 nm. Evaluation of the Knudsen number showed that gas transport in the CCL is governed by the transition flow regime. The liquid water transport can be described within continuum hydrodynamics by including suitable slip flow boundary conditions. 展开更多
关键词 Cathode catalyst layer (CCL) polymer electrolyte fuel cell (PEFC) tomograph three-dimensional reconstruction
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Nanostructured ultrathin catalyst layer with ordered platinum nanotube arrays for polymer electrolyte membrane fuel cells 被引量:10
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作者 Ruoyi Deng Zhangxun Xia +2 位作者 Ruili Sun Suli Wang Gongquan Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第4期33-39,共7页
Fabrication of novel electrode architectures with nanostructured ultrathin catalyst layers is an effective strategy to improve catalyst utilization and enhance mass transport for polymer electrolyte membrane fuel cell... Fabrication of novel electrode architectures with nanostructured ultrathin catalyst layers is an effective strategy to improve catalyst utilization and enhance mass transport for polymer electrolyte membrane fuel cells (PEMFCs).Herein,we report the design and construction of a nanostructured ultrathin catalyst layer with ordered Pt nanotube arrays,which were obtained by a hard-template strategy based on ZnO,via hydrothermal synthesis and magnetron sputtering for PEMFC application.Because of the crystallographically preferential growth of Pt (111) facets,which was attributed to the structural effects of ZnO nanoarrays on the Pt nanotubes,the catalyst layers exhibit obviously higher electrochemical activity with remarkable enhancement of specific activity and mass transport compared with the state-of-the-art randomly distributed Pt/C catalyst layer.The PEMFC fabricated with the as-prepared catalyst layer composed of optimized Pt nanotubes with an average diameter of 90(±10) nm shows excellent performance with a peak power density of 6.0W/mgPt at 1 A/cm^2,which is 11.6%greater than that of the conventional Pt/C electrode. 展开更多
关键词 catalyst layer Membrane electrode assembly PLATINUM NANOTUBE arrays fuel cells
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In situ grown nanoscale platinum on carbon powder as catalyst layer in proton exchange membrane fuel cells(PEMFCs) 被引量:2
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作者 Sheng Sui Xiaolong Zhuo +4 位作者 Kaihua Su Xianyong Yao Junliang Zhang Shangfeng Du Kevin Kendall 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第3期477-483,共7页
An extensive study has been conducted on the proton exchange membrane fuel cells (PEMFCs) with reducing Pt loading. This is commonly achieved by developing methods to increase the utilization of the platinum in the ... An extensive study has been conducted on the proton exchange membrane fuel cells (PEMFCs) with reducing Pt loading. This is commonly achieved by developing methods to increase the utilization of the platinum in the catalyst layer of the electrodes. In this paper, a novel process of the catalyst layers was introduced and investigated. A mixture of carbon powder and Nafion solution was sprayed on the glassy carbon electrode (GCE) to form a thin carbon layer. Then Pt particles were deposited on the surface by reducing hexachloroplatinic (IV) acid hexahydrate with methanoic acid. SEM images showed a continuous Pt gradient profile among the thickness direction of the catalytic layer by the novel method. The Pt nanowires grown are in the size of 3 nm (diameter) x l0 nm (length) by high solution TEM image. The novel catalyst layer was characterized by cyclic voltammetry (CV) and scanning electron microscope (SEM) as compared with commercial Pt/C black and Pt catalyst layer obtained from sputtering. The results showed that the platinum nanoparticles deposited on the carbon powder were highly utilized as they directly faced the gas diffusion layer and offered easy access to reactants (oxygen or hydrogen). 展开更多
关键词 PLATINUM catalyst layer carbon powder layer proton exchange membrane fuel cells
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Pt-Ru Catalysts Prepared by a Modified Polyol Process for Direct Methanol Fuel Cells 被引量:1
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作者 ZHANG Junmin ZHU Fangfang +2 位作者 ZHANG Kunhua LIU Weiping GUAN Weiming 《贵金属》 CAS CSCD 北大核心 2012年第A01期222-226,共5页
Supported PtRu/C catalysts used in direct methanol fuel cells (DMFCs) were prepared by a new modified polyol method. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and cyclic voltammograms (CVs) were ... Supported PtRu/C catalysts used in direct methanol fuel cells (DMFCs) were prepared by a new modified polyol method. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and cyclic voltammograms (CVs) were carried out to characterize the morphology, composition and the electrochemical properties of the PtRu/C catalyst. The results revealed that the PtRu nanoparticles with small average particle size (≈2.5 nm), and highly dispersed on the carbon support. The PtRu/C catalyst exhibited high catalytic activity and anti poisoned performance than that of the JM PtRu/C. It is imply that the modified polyol method is efficient for PtRu/C catalyst preparation. 展开更多
关键词 PtRu/C catalysts modified polyol method direct methanol fuel cells(DMFCs) electrochemical performance
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Paper-like Microfibrous Nickel Catalyst for Hydrogen Production via NH_3 Decomposition in Fuel Cell Applications
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作者 Yong LU Hong WANG Ye LIU Ming Yuan HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第10期1397-1400,共4页
A sinter-locked three-dimensional network of microfibrous nickel catalyst has been fabricated based on wet layup papermaking and sintering processes and this novel approach permits the production of -11 W fuel cell po... A sinter-locked three-dimensional network of microfibrous nickel catalyst has been fabricated based on wet layup papermaking and sintering processes and this novel approach permits the production of -11 W fuel cell power H2 via NH3 decomposition with a conversion of 97% at 750 ℃ in a bed of 0.6 cm^3. 展开更多
关键词 Microfibrous catalyst NICKEL hydrogen production AMMONIA fuel cells.
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Iron and Nitrogen containing Carbon Catalysts with Enhanced Activity for Oxygen Reduction in Proton Exchange Membrane Fuel Cells
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作者 Chitturi Venkateswara Rao Lingam Hima Kumar Balasubramanian Viswanathan 《Open Journal of Physical Chemistry》 2011年第1期11-22,共12页
Iron and nitrogen containing carbon catalysts were prepared by the pyrolysis of iron (III) tetramethoxyphenylporphyrin complex adsorbed on as-received as well as nitric acid treated carbon black and employed them as o... Iron and nitrogen containing carbon catalysts were prepared by the pyrolysis of iron (III) tetramethoxyphenylporphyrin complex adsorbed on as-received as well as nitric acid treated carbon black and employed them as oxygen reduction electrodes for hydrogen-oxygen PEM fuel cells. The influence of carbon surface functional groups on the dispersion of active species and electrocatalytic performance is investigated using electron microscopic and electrochemical techniques. The existence of quinone functional groups on the nitric acid treated carbon was evident from X-ray photoelectron spectroscopy and cyclic voltammetry. Rotating disk electrode voltammetry results affirmed the good electrocatalytic activity and stability of pyrolyzed macrocyclic complex adsorbed on nitric acid treated carbon compared to that of as-received carbon. This is ascribed to the greater number of Fe/N active species as well as good dispersion of metal clusters over nitric acid treated carbon support. Fuel cell tests depicted the comparable performance of pyrolyzed complex adsorbed on nitric acid treated carbon with commercial Pt/C at 353 K. Durability measurements performed under fuel cell operating conditions for 120 h indicate the good stability of the catalysts. 展开更多
关键词 IRON-BASED CLUSTERS Non-Precious catalystS Oxygen Reduction PEM fuel cells
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Prospects and challenges of graphene based fuel cells 被引量:3
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作者 Muhammad Zahir Iqbal Assad-Ur Rehman Saman Siddique 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第12期217-234,共18页
Novel characteristics of graphene have captured great attention of researchers for energy technology applications.Incorporation of graphene related hybrid and composite materials have demonstrated high performance and... Novel characteristics of graphene have captured great attention of researchers for energy technology applications.Incorporation of graphene related hybrid and composite materials have demonstrated high performance and durability for fuel cell energy conversion devices.This article overviews graphene based materials for fuel cell technology applications such as electrodes additives,bipolar plates and proton conducting electrolyte membrane.The graphene dispersion over electrodes has revealed enhanced exposure of electrochemically active surface area for improved electro-catalytic activity towards fuel oxidation and oxidant reduction reactions.The issue of device stack durability and degraded performance due to corrosion of bipolar plates is discussed by incorporating graphene based materials.In proton exchange membrane devices,graphene as an electrolyte has shown an excellent performance towards high ionic conductivity and power density.The graphene incorporation in fuel cell devices has exhibited commendable performance and has bright future for commercial applications. 展开更多
关键词 GRAPHENE fuel cell ELECTRO-catalyst Power density DURABILITY
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Progress in portable direct methanol fuel cell
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作者 SHE Pei-liang HU Xin-guo +3 位作者 CHEN Huai-lin 佘沛亮 胡信国 陈怀林 《电池》 CAS CSCD 北大核心 2004年第3期215-216,共2页
The progresses in portable DMFC worldwide were reviewed, the current status of its components, catalysts, proton exchange membrane and flow field plate, the market development of portable electronic appliances, such a... The progresses in portable DMFC worldwide were reviewed, the current status of its components, catalysts, proton exchange membrane and flow field plate, the market development of portable electronic appliances, such as mobile phone, PDA and notebook were introduced. 展开更多
关键词 DMFC 燃料电池 正极 负极
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Modeling development on the meso-scale reacting transport phenomena in proton exchange membrane fuel cells 被引量:1
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作者 Jianliang Yuan Yu Xiao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第3期370-378,共9页
The catalyst layer (CL) of proton exchange mem-brane fuel cell (PEMFC) involves various particles and pores in meso-scale, which has an important effect on the mass, charge (proton and electron) and heat transpo... The catalyst layer (CL) of proton exchange mem-brane fuel cell (PEMFC) involves various particles and pores in meso-scale, which has an important effect on the mass, charge (proton and electron) and heat transport coupled with the electrochemical reactions. The coarse-grained molecular dynamics (CG-MD) method is employed as a meso-scale structure reconstruction technique to mimic the self-organization phenomena in the fabrication steps of a CL. The meso-scale structure obtained at the equilibrium state is further analyzed by molecular dynamic (MD) software to provide the necessary microscopic parameters for understanding of multi-scale and-physics processes in CLs. The primary pore size distribution (PSD) and active platinum (Pt) surface areas are also calculated and then compared with the experiments. In addition, we also highlight the implementation method to combine microscopic elementary kinetic reaction schemes with the CG-MD approaches to provide insight into the reactions in CLs. The concepts from CG modeling with particle hydrodynamics (SPH) and the problems on coupling of SPH with finite element modeling (FEM) methods are further outlined and discussed to understand the effects of the meso-scale transport phenomena in fuel cells. 展开更多
关键词 CG-MD · Meso-scale · Reaction · catalyst layer · fuel cell
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Nanoporous Silicon-Based Ammonia-Fed Fuel Cells
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作者 Tayyar D. Dzhafarov Sureyya Aydin Yuksel Mustafa Aydin 《Materials Sciences and Applications》 2014年第14期1020-1026,共7页
The objective of the paper is to report results on fabrication, structural, morphological and performance characteristics of novel TiO2/PS/Si, Au/TiO2/PS/Si and Au/PS/Si direct ammonia fuel cells (DAFC) using nanoporo... The objective of the paper is to report results on fabrication, structural, morphological and performance characteristics of novel TiO2/PS/Si, Au/TiO2/PS/Si and Au/PS/Si direct ammonia fuel cells (DAFC) using nanoporous silicon (PS) as proton conducting membrane (instead of traditional polymer Nafion membrane) and TiO2, Au/TiO2 or Au as catalyst layer. Porous silicon layers have been prepared by electrochemical modification of silicon substrates. Films containing titanium dioxide are more efficient catalysts for hydrogen production from ammonia solution. The Au/ TiO2/PS/Si cell exhibited the open circuit voltage 0.87 V and performance of 1.6 mW/cm2 with 50% ammonia solution as fuel at room temperature. Mechanisms of proton transport in nanoporous silicon membrane and generation of electricity in DAFC have been considered. Advantages of investigated direct ammonia fuel cells consist in simplicity of fabrication technology, which can be integrated into standard silicon micro fabrication processes and operation of cells at room temperature. The work demonstrates that the PS based fuel cells have potential for portable applications. 展开更多
关键词 NANOPOROUS Silicon Membrane fuel cell AU/TIO2 catalyst AMMONIA ELECTROLYTE Power Density
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Selective catalytic methanation of CO in hydrogen-rich gases over Ni/ZrO_2 catalyst 被引量:23
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作者 Qihai Liu Xinfa Dong Xinman Mo Weiming Lin 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第3期268-272,共5页
Ni/ZrO2 catalysts were prepared by the incipient-wetness impregnation method and were investigated in activity and selectivity for the selective catalytic methanation of CO in hydrogen-rich gases with more than 20 vol... Ni/ZrO2 catalysts were prepared by the incipient-wetness impregnation method and were investigated in activity and selectivity for the selective catalytic methanation of CO in hydrogen-rich gases with more than 20 vol% CO2. The result showed that Ni loadings significantly influenced the performance of Ni/ZrO2 catalyst. The 1.6 wt% Ni loading catalyst exhibited the highest catalytic activity among all the catalysts in the selective methanation of CO in hydrogen-rich gas. The outlet concentration of CO was less than 20 ppm with the hydrogen consumption below 7%, at a gas-hourly-space velocity as high as 10000 h-1 and a temperature range of 260 °C to 280 °C. The X-ray diffraction (XRD) and temperature programmed reduction (TPR) measurements showed that NiO was dispersed thoroughly on the surface of ZrO2 support if Ni loading was under 1.6 wt%. When Ni loading was increased to 3 wt% or above, the free bulk NiO species began to assemble, which was not favorable to increase the selectivity of the catalyst. 展开更多
关键词 selective methanation CO removal Ni/ZrO2 catalyst hydrogen-rich gases fuel cell
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Hydrogen production through diesel steam reforming over rare-earth promoted Ni/γ-Al_2O_3 catalysts 被引量:4
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作者 Lihao Xu Wanliang Mi Qingquan Su 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第3期287-293,共7页
Rare-earth (La, Ce, Yb) promoted Ni/γ-Al2O3 catalysts were prepared by impregnation method. Activity and carbon formation resistance of the prepared catalysts were evaluated under various reaction conditions. Catal... Rare-earth (La, Ce, Yb) promoted Ni/γ-Al2O3 catalysts were prepared by impregnation method. Activity and carbon formation resistance of the prepared catalysts were evaluated under various reaction conditions. Catalyst characterizations with TG, TPR and H2 chemisorption were carried out to investigate the promoting mechanism. Experimental results show that rare-earth promoters, especially Yb promoter, obviously improve the activity and carbon formation resistance of Ni/γ-Al2O3 catalyst, and Yb-Ni catalyst shows even higher performance than several commercial catalysts. According to the characterization results, Yb promoter enhances the interaction between the active metal and support, thus increasing the active metal's dispersion and improving its performance. Furthermore, the obvious difference in diesel conversion between Yb-Ni catalyst and others was shown in the temperature range of 450-550 °C, which would be the reason for its excellent carbon resistance. 展开更多
关键词 DIESEL steam reforming Ni catalysts rare-earth promoter fuel cell
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Solvent effects on Pt-Ru/C catalyst for methanol electro-oxidation 被引量:2
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作者 Jinwei Chen Chunping Jiang Hui Lu Lan Feng Xin Yang Liangqiong Li Ruilin Wang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第3期341-345,共5页
Alloying degree, particle size and the level of dispersion are the key structural parameters of Pt-Ru/C catalyst in fuel cells. Solvent(s) used in the preparation process can affect the particle size and alloying de... Alloying degree, particle size and the level of dispersion are the key structural parameters of Pt-Ru/C catalyst in fuel cells. Solvent(s) used in the preparation process can affect the particle size and alloying degree of the object substance, which lead to a great positive impact on its properties. In this work, three types of solvents and their mixtures were used in preparation of the Pt-Ru/C catalysts by chemical reduction of metal precursors with sodium borohydride at room temperature. The structure of the catalysts was characterized by X-ray diffraction (XRD) and Transmission electron microscopy (TEM). The catalytic activity and stability for methanol electro-oxidation were studied by Cyclic Voltammetry (CV) and Chronoamperometry (CA). Pt-Ru/C catalyst prepared in H2O or binary solvents of H2O and isopropanol had large particle size and low alloying degree leading to low catalytic activity and less stability in methanol electro-oxidation. When tetrahydrofuran was added to the above solvent systems, Pt-Ru/C catalyst prepared had smaller particle size and higher alloying degree which resulted in better catalytic activity, lower onset and peak potentials, compared with the above catalysts. Moreover, the catalyst prepared in ternary solvents of isopropanol, water and tetrahydrofuran had the smallest particle size, and the high alloying degree and the dispersion kept unchanged. Therefore, this kind of catalyst showed the highest catalytic activity and good stability for methanol electro-oxidation. 展开更多
关键词 solvent effect fuel cell methanol electro-oxidation Pt-Ru/C catalyst TETRAHYDROFURAN
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Effects of the Specific Area and the Thermal Stability of a Polymer on the Catalytic Activities of Polymer Immobilized Co-Pd Catalysts by SAMI 被引量:1
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作者 WU Shi-hua WEI Wei +5 位作者 ZHU Chang-ying HUANG Wei-ping ZHANG Shou-min ZHENG Xiu-cheng ZHANG Shu-hong ZHAO Wei-jun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第4期439-444,共6页
Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic meas... Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic measurement showed that as the specific area of the resin increased, the particle sizes of Co and Pd on the catalysts with the same metal content decreased, so the catalytic activity of the catalysts for the hydrogenation of diacetone alcohol as well as the reduction of oxygen on the fuel cell electrode increased. Below 140 , the conversion of diacetone alcohol increased as the reaction temperature increased, and above 140 , the conversion decreased because of the rupture of the resin. 展开更多
关键词 Cobalt-palladium catalyst Diacetone alcohol hydrogenation fuel cell electrode
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Nitrogen-Doped Carbon Nanotube-Supported Pd Catalyst for Improved Electrocatalytic Performance toward Ethanol Electrooxidation 被引量:3
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作者 Ying Wei Xinyuan Zhang +4 位作者 Zhiyong Luo Dian Tang Changxin Chen Teng Zhang Zailai Xie 《Nano-Micro Letters》 SCIE EI CAS 2017年第3期43-51,共9页
In this study, hydrothermal carbonization(HTC)was applied for surface functionalization of carbon nanotubes(CNTs) in the presence of glucose and urea. The HTC process allowed the deposition of thin nitrogen-doped carb... In this study, hydrothermal carbonization(HTC)was applied for surface functionalization of carbon nanotubes(CNTs) in the presence of glucose and urea. The HTC process allowed the deposition of thin nitrogen-doped carbon layers on the surface of the CNTs. By controlling the ratio of glucose to urea, nitrogen contents of up to 1.7 wt%were achieved. The nitrogen-doped carbon nanotube-supported Pd catalysts exhibited superior electrochemical activity for ethanol oxidation relative to the pristine CNTs.Importantly, a 1.5-fold increase in the specific activity was observed for the Pd/HTC-N1.67%CNTs relative to the catalyst without nitrogen doping(Pd/HTC-CNTs). Furtherexperiments indicated that the introduction of nitrogen species on the surface of the CNTs improved the Pd(0)loading and increased the binding energy. 展开更多
关键词 Direct alcohol fuel cells Hydrothermal carbonization Nitrogen-doped carbon nanotubes Pdbased catalyst Ethanol electrocatalyst
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Nanostructure and Formation Mechanism of Pt-WO_3/C Nanocatalyst by Ethylene Glycol Method
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作者 吴锋 吴川 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期377-383,共7页
Pt-WO3 nanoparticles uniformly dispersed on Vulcan XC-72R carbon black were prepared by an ethylene glycol method.The morphology,composition,nanostructure,electrochemical characteristics and electrocatalytic activity ... Pt-WO3 nanoparticles uniformly dispersed on Vulcan XC-72R carbon black were prepared by an ethylene glycol method.The morphology,composition,nanostructure,electrochemical characteristics and electrocatalytic activity were characterized,and the formation mechanism was investigated.The average particle size was 2.3 nm,the same as that of Pt/C catalyst.The W/Pt atomic ratio was 1/20,much lower than the design of 1/3.The deposition of WO3·xH2O nanoparticles on Vulcan XC-72R carbon black was found to be very difficult by TEM.From XPS and XRD,the Pt nanoparticles were formed in the colloidal solution of Na2WO4,the EG insoluble Na2WO4 resulted in the decreased relative crystallinity and increased crystalline lattice constant compared with those of Pt/C catalyst and,subsequently,the higher specific electrocatalytic activity as determined by CV.The Pt-mass and Pt-electrochemically-active-specific-surface-area based anodic peak current densities for ethanol oxidation were 422.2 mA·mg-1Pt and 0.43 mA·cm-2Pt,1.2 and 1.1 times higher than those of Pt/C catalyst,respectively. 展开更多
关键词 Pt-based catalyst tungsten oxide ethylene glycol method fuel cell
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Highly efficient Fe/N/C catalyst using adenosine as C/N-source for APEFC
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作者 Huan Ren Ying Wang +3 位作者 Xun Tang Juntao Lu Li Xiao Lin Zhuang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第4期616-621,共6页
An environmentally friendly precursor, adenosine, has been used as a dual source of C and N to synthesize nitrogen-doped carbon catalyst with/without Fe. A hydrothermal carbonization method has been used and water is ... An environmentally friendly precursor, adenosine, has been used as a dual source of C and N to synthesize nitrogen-doped carbon catalyst with/without Fe. A hydrothermal carbonization method has been used and water is the carbonization media. The morphology of samples with/without Fe component has been compared by HRTEM, and the result shows that Fe can promote the graphitization of carbon. Further electro-chemical test shows that the oxygen reduction reaction(ORR) catalytic activity of Fe-containing sample(C–Fe N) is much higher than that of the Fe-free sample(C–N). Additionally, the intermediates of C–Fe N formed during each synthetic procedure have been thoroughly characterized by multiple methods,and the function of each procedure has been discussed. The C–Fe N sample exhibits high electro-catalytic stability and superior electro-catalytic activity toward ORR in alkaline media, with its half-wave potential 20 mV lower than that of commercial Pt/C(40 wt%). It is further incorporated into alkaline polymer electrolyte fuel cell(APEFC) as the cathode material and led to a power density of 100 m W/cm;. 展开更多
关键词 N-doped carbon catalyst ORR fuel cell Alkaline polymer electrolyte Fe/N/C
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