Ternary CuZnPd Nanoalloys Achieving the Synergy of an Electronic Interaction and Bifunctional Catalysis for Efficient Ethanol Electrooxidation

Abstract

Rationally constructing nanoalloys achieving the synergy of multiple interactions among different constituents could substantially enhance the electrocatalytic performance of an active metal for a given chemical reaction. In this context, we design and synthesize well-controlled ternary CuZnPd alloy nanoparticles, in which the Cu atoms modify the electronic configuration of Pd atoms through the ligand effect or the lattice strain effect, while the Zn atoms clean their neighboring Pd sites through a bifunctional mechanism, and the synergy of these two benefits endows the ternary CuZnPd alloy nanoparticles with exceptional electrocatalysis for a room-temperature ethanol oxidation reaction (EOR). In specific, at an appropriate 1/1/1 molar ratio for Cu/Zn/Pd, the as-prepared ternary CuZnPd alloy nanoparticles exhibit both the highest specific activity and mass activity of 17.3 mA cm–2 and 11.8 A mg–1, respectively, which outperform those of their CuPd, ZnPd alloy counterparts and the commercial Pd/C catalyst, as well as the majority of recently reported Pd-based catalysts. Density functional theory calculations verify that the key CO* and CH3CHO* intermediates generated during the EOR have the lowest adsorption energy on the ternary CuZnPd alloy nanoparticles, which is responsible for their boosted EOR electrocatalysis.