Electrocatalytic Activity of Graphene-Supported Pt-Cu Catalysts Prepared by an Impregnation Method for Ethanol Oxidation

Compared with traditional energy, direct ethanol fuel cells (DEFCs) have some apparent advantages such as low reaction temperature (<100°C), easy storage and transportation of fuel, high energy efficiency, and little pollution to the environment. Therefore, DEFCs ar e considered to be one of the ideal renewable energy resources with a promising prospect for commercial applications. Despite these advantages, there are still some critical obstacles inhibiting broad applications of DEFCs. The performance of fuel cells largely depends on anode and cathode reactions, which are substantially affected by the activity of expensive noble Pt catalysts. Consequently, different Pt-based bimetallic and trimetallic catalysts have been extensively investigated to replace pure Pt catalysts [1], and novel carbon materials have been explored as catalyst support s to effectively disperse catalyst particles [2]. In this study, graphenesupported Pt/Cu and Pt nanoparticles were synthesized by an impregnation method followed by a heat treatment in H2 atmosphere, and their electrocatalytic activities were measured for ethanol oxidation. For the synthesis of graphene-supported Pt [3], one mg of H2PtCl6·xH2O was mixed with 20 mg of graphene, which was dispersed in 10 µl of acetone solution, and ultra-sonicated for 30 min. The resulting slurr y was dried in a convection oven at 100 °C for 10 h to allow the evaporation of acetone. The mixture was then treated with 4% H2 in Ar gas at 250 °C for 3 h. For the synthesis of graphene-supported Pt/Cu, the only difference was to add 0.33 mg of CuCl2 to the solution of graphene and Pt precursor.