Copper-enriched palladium-copper alloy nanoparticles for effective electrochemical formic acid oxidation

In this work, Pd-Cu alloy nanoparticles (NPs) with different atomic ratios are prepared on functionalized carbon nanotubes (CNTs) and applied as electrocatalysts for formic acid oxidation. The Cu-enriched Pd-Cu alloy NPs exhibit improved electrocatalytic activity and stability. Functionalized carbon supports are applied as substrates to tune the nanoscale morphologies of the obtained bimetallic phases under appropriate calcination and hydrogenation treatments. Spill-over effect aids a reduction of a high weight loading of Cu in its metallic phase, in turn, these Cu atoms integrate into Pd lattice and isolate Pd neighbouring atoms. Surface analyses show that a certain amount of the isolated Pd remains on the surfaces of Pd-Cu alloy NPs, which is responsible for the enhanced electrocatalytic performance.