采用自设计的特制H 形电解槽模拟单个氢 空气质子交换膜燃料电池运作,并以电化学方法、SEM及XRD等技术研究两种商用催化剂,即碳载铂(Pt/C)和纯铂钌(Pt Ru)的电催化活性、表面形貌及其结构和寿命.同时对比了两种催化剂分别放在H 形电解槽和常规电解槽中运行情况的测试结果.实验表明,经过H 形电解槽运行后的催化剂,其循环伏安曲线表征氢吸脱的特征峰分别发生了正偏移(Pt/C电极)和负偏移(Pt Ru电极),且对应的峰电流呈现减小的趋势(特别是Pt/C电极).一氧化碳的毒化造成纯铂钌的电催化活性显著下降,其影响是不可逆的.
A particularly designed H-type cell was used to simulate the operating condition of a hydrogen-air proton exchange membrane fuel cell (PEMFC). The electrocatalytic activity, morphology, structure and lifetime of commercially available catalysts, carbon support platinum (Pt/C) and unsupported platinum-ruthenium (Pt-Ru), were preliminary studied by carrying out electrochemical measurements and by SEM, XRD techniques. The catalysts were simultaneously tested in the H-cell under operation, and also separately tested in a conventional electrochemical cell for comparison. It was found that the characteristic peaks of hydrogen adsorption/desorption on cyclic voltammograms shifted considerably to a more positive direction for Pt/C, while a more negative direction for Pt-Ru. The magnitude of the peak current densities on CV curves, especially observed from Pt/C catalyst, tended to reduce after the lifetime tests. The electrocatalytic activity of Pt-Ru was significantly lower due to carbon monoxide poison, and the effect of CO on catalyst was irreversible.
[1] RenX,PiotrZ,SharonT,etal.RecentadvancesindirectmethanolfuelcellsatLosAlamosNationalLaboratory[J].J.PowerSources,2000,86:111~116.
[2] GamburzevS.ApplebyAJ.Recentprogressinperformanceimprovementoftheprotonexchangemembranefuelcell(PEMFC)[J].J.PowerSources,2002,107:5~12.
[3] AntoliniE.Formationofcarbon supportedPtMalloysforlowtemperaturefuelcells:areview[J].Mater.Chem.Phys.,2003,78:563~573.
[4] Lizcano ValbuenaWH,PaganinVA,GonzalezER.Methanolelectro oxidationongasdiffusionelectrodespreparedwithPt Ru/Ccatalysts[J] .ElectrochimicaActa,2002,47:3715~3722.
[5] DinhHN,RenX,GarzonFH,etal.Electrocatalysisindirectmethanolfuelcells:in situprobingofPtRuanodecatalystsurfaces[J].J.Electroanaly.Chem.,2000,491:222~233.
[6] LeeS,ParkK,ChoiJ,etal.NanoparticlesSynthesisandelectrocatalyticactivityofPtalloysfordirectmethanolfuelcells[J].J.Electrochem.Soc.,2002,149:A1304.