Biomimetic Non‐Coplanar Multilayer Defense Architecture Achieves High Current Density Chloride‐Resistant Seawater Oxidation
Jinke Shen, Shuo Yan, Hongyu Mi, Fengjiao Guo, Haiyan Jin, Liming Jin
Abstract
Abstract Rational design of highly active and Cl − ‐tolerant electrocatalysts for the oxygen evolution reaction (OER) is critical to enabling practical seawater electrolysis for hydrogen production. Herein, a novel MCF‐LDH catalyst with a biomimetic ‘Clam‐Shield’ multilevel defense system is synthesized via hydrothermal and in situ redox methods. The innovative z ‐axis non‐coplanar architecture of functional layers enables synergistic chloride resistance via physical blocking (MnO 2 barrier) and electrostatic repulsion (CO 3 2− interlayers). Density functional theory (DFT) calculations elucidate that the MnO 2 modulates the d ‐band center of CoFe‐LDH, while the catalyst exhibits a pronounced thermodynamic preference for OH − adsorption (−1.89 eV) over Cl − (−0.35 eV), thereby stabilizing critical reaction intermediates. Furthermore, the density of states (DOS) analysis of MCF‐LDH reveals enhanced continuity of Fe‐3 d and Co‐3 d orbitals near the Fermi energy ( E f ), indicating improved electronic conductivity. This ‘axial dislocation‐functional synergy’ strategy endows MCF‐LDH with exceptional electrocatalytic performance, delivering low overpotentials of 277 and 304 mV at 300 and 500 mA cm −2 , respectively. Moreover, the MCF‐LDH catalyst presents outstanding long‐term stability, retaining 99.4% and 97.8% of its initial activity after 600 h at high current densities of 500 and 1000 mA cm −2 in alkaline seawater electrolyte. This study provides a promising design strategy for chloride‐resistant OER electrocatalysts.