Ultrathin Heterogeneous Nanolayer Structure of Feconicu Multi-Principal Element Alloy for Robust Water Electrolysis

Abstract

Developing efficient, cost-effective alloy catalysts for the hydrogen evolution reaction (HER) is a promising strategy to convert electrical energy to chemical fuels efficiently, however, it remains challenge. Herein, a designed non-equimolar FeCoNiCu multi-principal element alloys (MPEAs) catalyst, fabricated via a simple physical metallurgy and chemical dealloying, exhibits HER performance comparable to commercial noble metal counterpart. The optimal (FeCoNi)70Cu30 (at. %) catalysts display a remarkable minimum overpotential of 34 mV (@10 mA cm-2) and a Tafel slope of 48 mV dec-1. Meanwhile, the electrocatalyst exhibits excellent long-term durability stability at a high current density of −500 mA cm-2. This is attributed to the multi-scale substructure of distinctive, self-supporting Colosseum-inspired skeletal structure, coupled with nanoscale porous architecture attached to ultra-thin serrated amorphous nanolayer structure, significantly enhancing the specific surface and active sites. This study provides a novel strategy for designing high-performance non-precious metal catalysts with heterogeneous substructures based on multicomponent combinations.

Keywords: multi-principal element alloys, Dealloying, Electrocatalysis, hierarchical nanopore, Hydrogen evolution reaction