共查询到18条相似文献,搜索用时 78 毫秒
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本文主要探究在3种体系下制备Pt-Co/C催化剂,分别将这3种体系下制备的Pt-Co/C催化剂与传统的Pt/C催化剂进行性能比较。结果表明:在乙二醇体系下得到的Pt-Co/C催化剂具有更好的效果,比传统的Pt/C催化剂的电催化氧化活性要好。 相似文献
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应用恒电位沉积法制得Pt、Ru和PtRu直接甲醇燃料电池阳极催化剂,并对三种催化剂的甲醇氧化活性和稳定性进行了考察。动电位和恒电位实验结果均表明,Ru的加入使PtRu的甲醇起始氧化电位相对于Pt催化剂负移,催化活性和稳定性得到明显的改善。 相似文献
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通过对Pt-Ru/WO3电极的制备及其催化活性研究。在Pt/WO3电极的基础上加入钌元素,能较大地提高低温氧化甲醇的活性和稳定性,是一种有潜力的甲醇直接氧化燃料电池的阳极催化剂。 相似文献
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采用TiO2溶胶法,在不同条件下制备了碳载Pt-TiO2催化剂。运用循环伏安法、线性扫描法和计时电流法来检测甲醇在不同方法制备的碳载Pt-TiO2催化剂上的电催化氧化情况。结果发现,在酸性溶液中方法a制备的碳载Pt-TiO2催化剂对甲醇的电氧化有良好的催化活性和稳定性。 相似文献
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以Pd Cl2和Co(NO3)2为原料,采用分步乙二醇还原法制备了多壁碳纳米管负载Pd-Co复合纳米催化剂Pd-Co/CNT。利用TEM、XRD和XPS对催化剂的结构进行了表征,考察了其甲醇电氧化性能。结果显示,Co的引入使Pd催化剂的分散性得到改善,其电化学表面积可达39.7 m2/g。循环伏安测试表明,当Pd∶Co物质的量比为1∶0.2时,Pd-Co/CNT的甲醇氧化峰电流密度约为Pd/CNT的2.7倍。计时电流结果表明,Co的添加使催化剂的活性衰减比例由Pd/CNT的63.8%降至54.2%,显示出较强的抗中毒能力。Pd-Co复合催化剂性能的改善归因于Pd与Co之间的协同相互作用。 相似文献
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Characterization of different Pt/Metal/Complex catalysts as anode catalysts for the PEM fuel cell 总被引:5,自引:0,他引:5
Different Pt/Me/Pc and Pt/Me/Complex catalysts (with Me=Metal: Co, Ni, and Pc=phthalocyanine) were synthesized by an impregnation method. A commercially available platinum catalyst purchased from E-TEK. was impregnated with solutions of cobalt phthalocyanine (CoPc) and nickel phthalocyanine tetrasulfonic salt (NiPc). After the reaction, part of the catalyst was heat treated at 700°C under nitrogen atmosphere. The resulting catalysts were structurally and electrochemically characterized before (Pt/Me/Pc) and after heat treatment (Pt/Me/Complex). The Pt/Me/Pc had an average particle size of about 3nm, while the average size after heat treatment increased to about 7nm. The composition of the different catalysts was about 80at platinum and 20at of the second metal (Co or Ni), and was verified with EDXS. In single fuel cell tests the best electrocatalytic activity was observed for the Pt/Ni/Complex system. 相似文献
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The feasibility of using poly(3,4-ethylenedioxythiophene) (PEDOT) as Pt catalyst support for direct methanol fuel cell (DMFC)
anodes was investigated. Measurements with freshly prepared Pt-PEDOT/C electrodes showed poor activity for methanol oxidation
in a half-cell and a DMFC. A substantial enhancement in that activity was evident after either electrochemical over-oxidation
of PEDOT or long-time storage of the Pt-PEDOT/C gas diffusion electrode (GDE) in air. Both procedures led to a reorganization
and increase in porosity of the reaction layer, which obviously contributed to better methanol accessibility to Pt catalyst
active centres. The effects of electrochemical activation and long-time storage in air on the morphology and elementary composition
of the Pt-PEDOT layer were investigated by means of Hg porosimetry and SEM/EDAX. It was found that the increase in porosity
was due to degradation of PEDOT characterized by a significant depletion of sulphur and oxygen in the conducting polymer matrix. 相似文献
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Guiyan Yu Weixiang Chen Jie Zhao Qiulin Nie 《Journal of Applied Electrochemistry》2006,36(9):1021-1025
Pt/C electrocatalysts were prepared from a solution of H2PtCl6 in ethylene glycol in the presence of XC-72 carbon by adding a small amount of sodium acetate as stabilizer. Repeated TEM images showed that the platinum nanoparticles were small and uniform in size and highly dispersed on XC-72 carbon supports when a small amount of sodium acetate solution was added to the synthesis solution. The Pt/C electrocatalysts exhibited very high electrocatalytic activity for liquid methanol oxidation. The effects of adding acetate on Pt particle size and size distribution are discussed. It is demonstrated that acetate can be used as a good stabilizer for preparing Pt/C catalyst with fine and uniform Pt particles. 相似文献
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G. Fóti C. Mousty K. Novy Ch. Comninellis V. Reid 《Journal of Applied Electrochemistry》2000,30(2):147-151
Platinum coatings on Ti were prepared by a two-step process: partial thermal decomposition of chloroplatinic acid followed by electroreduction of the coating. Effects of preparation temperature and of cathodic polarization on the roughness factor were studied. Roughness factors greater than 570 were achieved, leading to an enhancement of the activity towards isopropanol electrooxidation in 1M H2SO4. 相似文献
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以九水合硝酸铁为铁源,葡萄糖为炭源,通过水热法制备了FexOy@C复合材料。以该材料为载体,采用浸渍法制备了FexOy@C负载Pt催化剂,用于硝基化合物加氢制备相应苯胺。采用XRD和TEM对催化剂进行表征并探讨了催化剂的加入量、有机溶剂、混合溶剂体积比等因素对对氯硝基苯加氢制备对氯苯胺的影响。实验证明,该催化剂稳定性高,催化剂循环利用6次以后,其加氢活性仍可以达到100%,选择性可达99%以上。另外,该催化剂对其它硝基化合物也显示了较好的催化性能。 相似文献
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We have developed a porous-microelectrode (PME) to investigate the electroactivity of catalyst particles for proton exchange membrane fuel cells. The cavity at the tip of the PME was filled with Pt/C catalysts prepared by impregnation method. Cyclic voltammograms (CVs) recorded in 1 N H2SO4 aqueous solution revealed that the active area of the stacked catalysts exist not only at the surface but also inside of the stack. For methanol electrooxidation, 30 wt.% Pt/C exhibited the highest electroactivity, whereas the 50 wt.% Pt/C showed extremely small current. The small current is considered as a result of a small active-surface area. Methanol oxidation peak potential shifted toward cathodic direction as Pt-loading decreased, which agrees well with the Pt-oxide formation potential. The activation energy for methanol oxidation was assessed to be 44±3 kJ mol−1 for all Pt/C catalysts and Pt-disc electrode. 相似文献
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PtRu nanoparticles supported on nitrogen-doped multiwalled carbon nanotubes as catalyst for methanol electrooxidation 总被引:1,自引:0,他引:1
Raghuram Chetty Shankhamala Kundu Michael Bron Wolfgang Schuhmann Valentin Chirila Thomas Reinecke 《Electrochimica acta》2009,54(17):4208-108
Nitrogen-doped carbon nanotubes (N-CNT) obtained by plasma treatment were compared to the conventional acid-treated carbon nanotubes (O-CNT) as catalyst support for platinum-ruthenium (PtRu) nanoparticles in the anodic oxidation of methanol in direct methanol fuel cells. PtRu catalysts were prepared by an impregnation-reduction method from chloride precursors with metal loadings of 20 wt.%, and were characterised by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and electrochemical methods. Voltammetry and chronoamperometry studies showed that the performance of PtRu/N-CNT was significantly higher compared to PtRu/O-CNT and also to the commercial E-TEK PtRu/C catalyst, indicating that N-CNT are an interesting support material for fuel cell electrocatalyst. Nitrogen plasma treatment produced pyridinic and pyrrollic species on the CNT surface, which acts as the anchoring sites for the deposition of PtRu particles. A mechanism for the deposition of PtRu on N-CNT is tentatively proposed and discussed. 相似文献
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Pt/C催化剂制备方法的选择 总被引:1,自引:0,他引:1
研究了以HCl酸洗、H_2O_2、浓H_2SO_4、HNO_3氧化处理后的活性炭为载体,用不同方法制备了Pt担载量为3%的担载型Pt/C催化剂。TEM统计结果表明,HCl酸洗、HNO_3氧化活性炭为载体,甲醛还原法制备的催化剂分散度最高,平均粒径最小为2.2nm。FT-IR结果表明,HNO_3氧化处理活性炭,活性炭表面含氧基团明显增加。 相似文献