【摘要】 质子交换膜燃料电池阴极需要使用高活性的电催化剂来加速氧还原反应(ORR)速率,而提高活性成分贵金属铂(Pt)的功能反应利用率可解决其关键问题。本工作利用过渡金属钴Co(Ⅱ)-有机框架(Co-MOF)为前驱体合成ORR催化剂载体Co/C,并采取浸渍-液相还原法负载Pt纳米粒子制备了合金Pt-Co/C催化剂。通过对样品的孔隙结构、物相结构、微观形貌等表征,证实了载体Co/C具有较大的比表面积和相互连通的分级介孔结构,其独特的形貌、丰富的孔隙结构使负载的Pt纳米颗粒均匀分布、粒径范围窄,平均粒径约为6.8 nm。进一步对催化剂进行电化学性能评价,其电化学活性表面积(ECSA)接近于商用Pt/C催化剂的值,结果表明合金催化剂中活性成分Pt具有较高的利用率,同时还表现出载体独特的孔隙结构优势。更多还原

【Abstract】 The cathode of proton exchange membrane fuel cells need to use highly active electrocatalyst to accelerate the oxygen reduction reaction(ORR), and the key problem can be solved by improving the functional reaction utilization rate of the active component precious metal platinum. In this work, the ORR catalyst carrier Co/C was prepared through the transition metal cobalt-organic framework(Co-MOF) as the precursor, and the alloy Pt-Co/C catalysts was prepared by impregnation-liquid phase reduction method. The pore structure, phase structure, micromorphology and electrochemical properties of the samples were characterized and analyzed. The results show that the carrier Co/C has high specific surface area and interconnected hierarchical meso-porous structure. Its unique morphology and rich pore structure make the loaded platinum nanoparticles uniformly distributed, the particle size distribution range is narrow, and the average particle size is about 6.8 nm. Its electrochemical active surface area(ECSA) is close to the value of commercial Pt/C catalyst, which indicates that the active component platinum has high utilization rate in the alloy catalyst, meanwhile it shows the unique pore structure advantage of the carrier.更多还原