不同还原法制备的Pt-Co/C催化剂电催化还原性能

Electrocatalytic Reduction Performance of Pt-Co/C Catalysts Prepared by Different Reduction Methods

关键词:  直接甲醇燃料电池  电催化还原  浸渍还原法  甲醇  Pt-Co/C催化剂

Key words:  direct methanol fuel cell  cathode catalyst  electrocatalytic reduction  methanol  Pt-Co/C catalyst

摘要:

为寻求一种较好的Pt-Co/C纳米合金催化剂合成方法，运用浸渍还原法制备两种Pt-Co/C催化剂，运用循环伏安和线性扫描的方法测试它们在H₂SO₄溶液中有无CH₃OH时，对O₂的电催化还原情况及抗甲醇性能，同时与商用Pt/C催化剂进行还原性能比较。结果表明：与商用Pt/C催化剂电极相比，Pt-Co/C (1)催化剂电极对O₂的电催化还原效果较好。80℃时制备的Pt∶Co＝3∶1的Pt-Co/C催化剂电极对O₂的电催化还原效果最佳。扫描电子显微镜(Scanning Electron Microscope，SEM)和透射电子显微镜(Transmission Electron Microscope，TEM)观察表明，Pt-Co/C (1)催化剂粒径小且分散均匀。采用浸渍还原法，以硼氢化钠为还原剂制得的Pt-Co/C (1)催化剂对O₂的电催化还原性能较好，同时具有较好的抗甲醇氧化能力。

Abstract:

In order to find a better synthesis method of Pt-Co/C nano-alloy catalyst,two kinds of Pt-Co/C catalysts were prepared by impregnation reduction method,and their electrocatalytic reduction of O₂ and methanol resistance were tested by cyclic voltammetry and linear scanning in H₂SO₄ solution with or without CH₃OH.At the same time,their reduction performance was compared with that of Pt/C commercial catalysts.The results showed that Pt-Co/C (1) catalyst electrode has better electrocatalytic reduction effect on O₂ compared with Pt/C commercial catalyst electrode.The Pt-Co/C catalyst electrode with Pt∶Co=3∶1 prepared at 80℃ has the best electrocatalytic reduction effect on O₂.Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) observations showed that Pt-Co/C (1) catalyst particle size was small and well dispersed.Pt-Co/C (1) catalyst prepared by impregnation reduction method with sodium borohydride as reducing agent has good electrocatalytic reduction performance for O₂ and good resistance to methanol oxidation.