Pt纳米催化剂在质子交换膜燃料电池催化层中的尺寸效应研究

Particle Size Effects of Pt Nanocatalyst in the Catalyst Layer of Proton Exchange Membrane Fuel Cell

以XC-72碳黑为载体,H2[PtCl6]为前驱体,采用浸渍还原法并结合后续高温处理,制备出不同尺寸Pt颗粒(3～8nm)的Pt/C催化剂.在基于质子交换膜燃料电池(PEMFC)单电池的电化学电解池中,对实际PEMFC催化层中燃料电池反应的Pt催化剂尺寸效应进行了研究.结果表明,在PEMFC催化层环境中,Pt/C纳米催化剂对氢氧化和氧还原反应均有显著的粒度尺寸效应.随着Pt粒度减小,氢氧化和氧还原反应的表面积活性均降低.

Pt/C electrocatalysts with different Pt particle sizes （3-8 nm） were prepared using the impregnation-reduction method with H2[PtCl6] as precursor and vulcan XC-72 carbon black as support, The prepared Pt/C catalysts were used to evaluate the size effect of Pt on the kinetics of fuel cell reactions in the real catalyst layer of proton exchange membrane fuel cell （PEMFC） using a modified PEMFC single cell. The results indicate that the size of Pt nanocatalyst has significant impacts on the kinetics of hydrogen oxidation reaction （HOR） and oxygen reduction reaction （ORR） in the catalyst layer of PEMFC. With decreased Pt particle size, the specific activities of HOR and ORR decrease.