Enhanced oxygen evolution reaction performance of Cr-CoFe-layered double hydroxide via the synergistic roles of Fe etching, Cr doping, and anion intercalation

The development of cost-effective and efficient electrocatalysts for water electrolysis is crucial for sustainable hydrogen production. In this study, we designed a hierarchical Cr-CoFe-LDH composite using a tailored etching and doping strategy to enhance catalytic performance. By integrating mesoporous CoFe-LDH layers with C₂O₄^2- anions and Cr dopants, we engineered a structure that optimizes mass transport, strengthens electronic interactions at active sites, and stabilizes key catalytic species. In situ spectroscopic analysis provided direct evidence of active species evolution, offering insights into the underlying reaction mechanisms. As a result, the Cr-CoFe-LDH catalyst exhibited excellent oxygen evolution reaction (OER) activity, demonstrating enhanced intrinsic performance and long-term stability. This work presents a novel approach to designing high-performance LDH-based catalysts and advances the understanding of active site modulation for efficient water electrolysis.