溶胶法制备一种高效稳定Pt/GC催化剂及其电化学性能表征

Preparation of a High Efficiency and Long Durability Pt/GC Catalyst by Sol-gel Method and Its Electrochemical Properties

采用溶胶法制备了一种石墨化碳负载贵金属Pt的燃料电池氧还原催化剂(Pt/GC),并通过XRD、TEM、Raman和XPS等分析测试技术对其结构和组成进行了表征。测试结果表明这种新型催化剂中Pt颗粒粒径大约为2~3 nm且分散均匀。同时,通过线性扫描伏安法(LSV)和循环伏安法(CV)评价了这种催化剂的催化性能,加速耐久性实验(AAT)评价了其电化学稳定性和环境耐受性。电化学测试结果表明以石墨化碳为碳载体的催化剂在较低的铂载量下也能保持较高的催化活性和稳定性:经过1 000圈电化学循环伏安加速老化实验后,Pt/GC催化剂的半波电势仅降低了10 mV,而商业Pt/C催化剂的半波电势降低了47 mV。

A graphitized carbon-supported Pt catalyst(Pt/GC)was prepared by the sol-Gel method.The structure and compositions of this novel catalyst were characterized by XRD,TEM,Raman,and XPS,respectively.The experimental results show that the particle size of Pt particles in the Pt/GC catalyst is about 2~4 nm and the particles are uniformly dispersed.Moreover,the catalytic performance of catalyst was evaluated by linear sweep voltammetry(LSV)and cyclic voltammetry(CV),and the electrochemical stability and environmental resistance of the catalyst were evaluated by accelerated durability test(AAT).Electrochemical test results show that this catalyst can also maintain high catalytic activity and stability under low platinum loading:after 1 000 cycles of electrochemical cyclic voltammetry accelerated aging tests,the half-wave potential of the Pt/GC catalyst is only reduced by 10 mV while the commercial Pt/C catalyst is decayed by 47 mV.