Two Birds with One Stone: Contemporaneously Boosting OER Activity and Kinetics for Layered Double Hydroxide Inspired by Photosystem II

Abstract

AbstractThe poor catalytic kinetics together with unsatisfied activity of nonprecious metal electrocatalysts for oxygen evolution reaction hamper their applications in industrial water electrolysis. Inspired by the oxygen evolution cluster of photosystem II in nature, Li+‐doped NiFe layered double hydroxide modified with carboxylate is constructed by in situ growth on Ni foam (NFCL(70)‐ LDH @ NF) via one‐pot redox synthesis. Herein, lithium acetate is introduced to regulate the electronic structure and improve proton transfer kinetics, thus “Two birds with one stone”. The targeted product exhibits highly improved OER performance in 1 M KOH at room temperature (159 and 224 mV at 10 and 100 mA cm−2), as well as dramatically decreased Tafel slope (47.9 mV dec–1). Control experiments and theoretical calculations uncover that the presence of Li+ modulates the local electronic structure and stabilizes the OOH* intermediate. Specifically, the carboxylate ligands serve as relays to promote proton transfer efficiency, which is similar to the concerted proton electrons transfer in photosystem II. Moreover, NFCL(70)‐ LDH @ NF maintains the excellent performance over a month under the simulated industrial condition. The exploration of high performance, triggered synergistically by Li+ doping and acetate‐modifying, sheds light on the design of organic–inorganic hybrid electrocatalysts for highly efficient OER.