超临界CO2/甲醇流体制备PtRu/石墨烯催化剂应用于甲醇氧化

采用一种有效、方便和环境友好的超临界方法将PtRu沉积在热解还原石墨烯上.在超临界CO2作用下,以H2PtCl6和RuCl3作为前驱体的铂钌纳米粒子均匀地分散在石墨烯表面,且平均尺寸为2.87 nm.生成的复合材料通过循环伏安法、计时电流法和CO溶出实验来进行研究.与用相同的方法制备的PtRu/炭黑（Vulcan XC-72）复合材料相比,PtRu/膨胀还原石墨烯对甲醇氧化的电催化活性和对CO电氧化活性有了很大的改善.实验结果显示,利用超临界流体可以很容易制备高活性的石墨烯负载型金属电催化剂.

Highly Dispersed Platinum-ruthenium/Graphene Catalysts Prepared in Supercritical Carbon Dioxide-methanol Solution and Their Use for Methanol Oxidation

In this article, we present a simple, effective, low temperature and environ- mental supercritical fluid （SCF） route for preparing graphene-supported metal nanopar- ticles. With the help of supercritical carbon dioxide （SC CO2）, PtRu nanoparticles with an average size of 2.87 nm were uniformly distributed on the surfaces of functionalized graphene sheets （FGSs） by the reduction of a mixture of H2PtCl6 and RuCl3 precursors. The catalytic property of the as-prepared composites was investigated by cyclic voltammetry, chronoamperometry and CO stripping. Compared with their carbon black （Vulcan XC-72） counterparts, the PtRu/FGSs composites showed considerably improved catalytic activity for methanol oxidation and electro-oxidation activity for CO stripping. The findings suggest that highly efficient graphene-supported metallic electrocatalysts can be fabricated by the supercriti- cal fluid method and graphene as a favorable electrocatalytic carrier, which has promising po- tential application in direct methanol fuel cells.