Rhodium decorated stable platinum nickel nanowires for effective ethanol oxidation reaction

Abstract

Direct ethanol fuel cells (DEFCs) are considered one of the most promising energy resources for portable power devices. The current mainstream catalysts used for DEFCs are Pt- or Pd-based, which facilitate the partial oxidation of ethanol to CH3CHO or CH3COOH, but not the C—C bond cleavage, which is the inevitable path for the complete oxidation of ethanol. In addition, most noble catalysts are easily poisoned by CO, shortening their lifespan and stability, thus inhibiting the practical application of the catalysts. Herein, we report a type of ultrathin trimetallic Pt/Ni/Rh nanowires with various Rh contents toward the ethanol oxidation reaction (EOR), and the optimized Pt6Ni2Rh3/C demonstrates a high mass activity of 1.16 A mgPt−1 as well as considerable stability, anti-CO poisoning ability, and complete ethanol oxidation selectivity. In addition, density functional theory calculations reveal that introducing Rh to bimetallic Pt/Ni endows the catalyst with a moderate intermediate adsorption capacity and enhanced C—C bond cleavage capacity, favorable for the complete oxidation of ethanol.