Enhancing Oxygen\nEvolution Reaction via a Surface\nReconstruction-Induced Lattice Oxygen Mechanism

Systematic control of surface reconstruction during catalysis\nremains\nchallenging. Particularly, inducing a surface structure reconstruction\nfollowing the lattice oxygen oxidation mechanism (LOM), which can\nreduce the overpotential in oxygen evolution reaction (OER) catalysts,\nhas not been extensively investigated. The mechanism of the OER of\ntransition-metal-oxide-based catalysts can be facilitated by manipulating\nthe local coordination structure to modulate the reactivity of lattice\noxygen. Herein, we report an in situ surface reconstruction strategy\nby doping F into LaNiO<sub>3</sub> to distort the NiO<sub>6</sub> octahedral\nsites, weaken the Ni–O bonds, and increase lattice oxygen reactivity\nduring OER. The as-prepared LaNiO<sub>2.9</sub>F<sub>0.1</sub> exhibits\nenhanced performances toward OER with a low overpotential of 320 mV\nat 10 mA cm<sup>–2</sup>, a small Tafel slope of 78 mV dec<sup>–1</sup>, and good long-term stability in alkaline media.\nComprehensive analysis reveals that the in situ self-reconstructed\nsurface favors the LOM pathway for the OER, resulting in a considerably\nimproved performance. These results demonstrate that the lattice oxygen\nacts as a switch for directing the OER mechanism, and further, controlling\nthe lattice oxygen reactivity emerges as a promising approach for\ndynamic self-reconstruction to highly active OER electrocatalysts.