Facile Synthesis of PtCuNi Nanohexapods as Active Electrocatalysts for Methanol Oxidation and Ethanol Oxidation

Abstract

The design of Pt-based alloy nanocatalysts with sufficient accessible surface areas and abundant active sites is important for their application in direct methanol fuel cells (DMFCs) and direct ethanol fuel cells (DEFCs). Here, we report a simple one-pot method for the preparation of PtCuNi hexapod nanocrystals. The conversion mechanism of the nanoparticles from rhombic dodecahedra to hexapods was investigated by time evolution experiments. Electrochemical tests demonstrated that the PtCuNi nanohexapods exhibited greatly elevated catalytic performance for methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR) under acidic conditions. Specifically, the PtCuNi nanohexapods have mass activities of 1.73 and 2.31 A mgPt–1 for MOR and EOR, which are 2.9 and 2.3 times higher than those of the commercial Pt/C catalyst, respectively. Moreover, the PtCuNi nanohexapods also exhibit enhanced electrocatalytic stability compared to Pt/C. This work provides an effective strategy for the rational construction of nanocrystals with desired morphologies and structures in the application of catalysis, energy, sensors, and other fields.