质子交换膜燃料电池Pt-Fe/C催化剂合成及性能

Study on preparation and characteristic of Pt-Fe/C catalyst for the proton exchange membrane fuel cell

用铁作掺杂元素,通过液相均相沉淀-气/固高温还原两段反应方法合成了碳载Pt-Fe合金电极催化剂。研究了三种碳载体(Vulcan XC-72、乙炔黑、松木炭)对催化剂合成的影响。采用TEM(透射电镜)、SEM(扫描电镜)技术对合金催化剂的物理性质进行了测试。结果表明,获得的Pt-Fe/C催化剂中合金催化剂在Vulcan XC-72碳载体中分布均匀,粒度约5 nm。通过单电池放电实验,研究了不同的载体、铂/铁原子比、热处理温度等对电池放电性能的影响,实验表明,在本实验条件下,用Vulcan XC-72作载体、Pt/Fe原子比为1∶1、热处理温度900 ℃时,电极催化性能较好。但电极稳定性实验发现,Pt-Fe合金催化剂电极在大电流下放电时,电极的稳定性不能达到满意效果,这方面的工作还有待进一步研究。

Carbon-supported Pt-Fe alloy and Pt catalyst were prepared by two-step reaction containing liquid deposit and gas-solid reducing. Three active carbon carriers were investigated. The results show that Vulcan XC-72 carbon carrier is provided with more property on particle size and uniformity than ethine black and active carbon. The physical property of the alloy catalysts was tested by TEM?SEM techniques and the effect of different carriers, atom ratio of platinum and iron, heat-treatment temperature on electrochemical performances were investigated. The results show that carbon-supported Pt-Fe alloy catalyst appears preferable catalytic activity when Vulcan XC-72 is used as carrier, the Pt: Fe atomic ratio is 1∶1, and heat-treatment temperature is 900 ℃. But it has been also found that the electrode stability is not much satisfied when single-cell using Pt-Fe/C as electrocatalyst discharge at high current density and further researches will be continued.