负载Pd_(0.8)Fe_(0.2)合金催化剂的氧还原催化性能

Catalytic performances of carbon supported Pd_(0.8)Fe_(0.2) alloy catalyst for oxygen reduction

以Pd(C_(5)H_(7)O_(2))2和Fe_(3)(CO)12为原料,1,6-己二醇为溶剂,采用回流技术制备了Pd_(0.8)Fe_(0.2)/C催化剂,并考察了其对氧还原反应(ORR)的催化活性。结果表明,所得样品呈面心立方结构,Fe固溶于Pd晶格,形成Pd-Fe合金。催化剂存在聚集现象,聚集颗粒大小较为均匀。在Pd/C中添加Fe明显提高了催化剂对ORR的催化活性,在Pd_(0.8)Fe_(0.2)/C催化剂上氧分子还原生成水遵循四电子机理。Fe的添加能改变Pd表面状态,减弱了Pd-Oads键能,促进了吸附氧的脱附和还原。

Pd(C_(5)H_(7)O_(2))2 and Fe_(3)(CO)12 were used as raw materials,and 1,6 hexanediol was used as solvent.Pd_(0.8)Fe_(0.2)/C catalyst was prepared by reflux technique,and the electrocatalytic activity for the oxygen reduction reaction(ORR)was evaluated.The results showed that the prepared sample is face-centered cubic structure and the Pd-Fe alloy is formed by the dissolution of Fe into the Pd lattice.There is aggregation phenomenon in the catalysts,and the size of the aggregated particles is uniform.The addition of Fe increased the catalytic activity of the catalysts for the ORR.The reduction of oxygen molecules to water on the Pd_(0.8)Fe_(0.2)/C catalyst followed the four-electron mechanism.The addition of Fe changed the surface state of Pd metal,weakened the Pd-Oads bond energy,and promoted the desorption and reduction of adsorbed oxygen.