In Situ Surface PtCu Alloying on Delafossite-type CuAlO2 as Electrocatalyst for Enhanced Methanol Oxidation

Abstract

Delafossite type oxide CuAlO2 as a highly efficient methanol oxidation reaction catalyst support has been investigated in this work. Utilizing the sustained release of copper from CuAlO2 layered structure, we developed a composite catalyst that was in situ formed PtCu alloy upon oxide via solvothermal method. Owing to the metal-support interaction between PtCu alloy and CuAlO2, abundant oxygen defects and adsorbed hydroxyl groups were generated on the surface of composite catalyst, which were verified by structural characterizations and surface analysis. Density functional theory simulation further revealed that the in situ formation of PtCu alloy accompanied with superficial defects dramatically changed the geometry and electronic structures of the composite catalyst, resulting in a higher mass activity (990 mA/mgPt), specific activity (3.30 mA cm−2 ECSA), and a superior reaction kinetics of MOR performance. This work proves delafossite type oxide CuAlO2 as a potential support to facilitate the anti-CO poisoning ability of Pt-based catalysts.