Surface Active‐Site Engineering of Low‐Noble‐Metal‐Alloyed Metallic Glass Catalyst for Boosting Water Electrolysis

Abstract

AbstractThe development of efficient, robust, and cost‐effective electrocatalysts remains a significant challenge for practical water electrolysis. Here, a metallic glass (MG)‐based catalyst with surface‐enriched Ir and Pt‐alloyed active sites, demonstrating superior electrocatalytic performance, is reported. The dealloyed catalyst, characterized by an Ir and Pt‐rich honeycombed nanoporous surface and an interior flexible MG substrate, can directly serve as a bifunctional electrode, enabling efficient hydrogen and oxygen evolution reactions with low overpotentials of 19 and 223 mV to achieve a current density of 10 mA cm−2, respectively. Notably, the mass activity of the catalyst surpasses that of commercial Pt/C and Ir/C catalysts by 13.9 and 16.5 times, respectively. Additionally, the catalyst exhibits exceptional stability with negligible activity decay even under an ampere‐level current density (i.e., ≥1 A cm−2). Theoretical calculations reveal the optimization of atomic configuration and regulation of electronic interactions through lattice strain induced by the co‐alloying of Ir and Pt, contributing to superior electrocatalytic performance. Furthermore, the unique honeycombed nanoporous architecture, shaped by the surface migration and enrichment of the noble metals, offers abundant active sites for accelerating the electrocatalytic reactions. This work presents a novel approach to cost‐effectively design high‐performance alloy catalysts by engineering surface catalytically active sites.