Synthesis of High-Entropy Alloy Nanoparticles Using Microwave-assisted Reduction and Investigation of Their Enhanced Electrochemical Hydrogen Evolution Activity

Abstract High-entropy alloys (HEAs) are fascinating materials for novel catalysts because of their broad compositional space, which is enabled by entropy-driven mixing. Herein, HEA nanoparticles (NPs) containing Fe, Co, Ni, Cu, and Pd were successfully synthesized on reduced graphene oxide (rGO) by microwave-assisted reduction. Compared with the corresponding monometallic catalysts, the quinary FeCoNiCuPd/rGO demonstrated greater electrocatalytic activity toward the acidic hydrogen evolution reaction (HER). Density functional theory calculations revealed that modification of the d-band center and the hydrogen affinity induced by multielemental mixing enhanced the HEA's electrocatalytic performance.