A Novel Biomimetic Catalyst with Mn<sub>4‐x</sub>Ni<sub>x</sub>CaO<sub>5</sub> Structure for Superior Oxygen Evolution Reaction
Xu Zhao, Zhibin Geng, Jianghao Wang, Qian Zhu, Zhiyu Shao, Ming Ya, Ying Yu, Liping Li, Shouhua Feng, Guangshe Li
Abstract
Abstract In natural plants, Mn 4 CaO 5 cluster with metal‐oxo “distorted chair”‐like structure exhibits excellent oxygen evolution activity. However, the performance of biomimetic oxygen evolution catalysts based on the Mn 4 CaO 5 ‐like structure is far inferior to expectations. Herein, Ca and Ni are first doped together into birnessite and constructed a “distorted chair”‐like structure unit Mn 4‐x Ni x CaO 5 in a birnessite‐like Ca‐Mn(Ni)‐O catalyst, the biomimetic Mn 4‐x Ni x CaO 5 unit efficiently activates lattice oxygen and boosts the O─O coupling in oxygen evolution reaction (OER), which allows the catalyst to perform superior OER activity with an outstanding overpotential of 184 mV at 300 mA cm −2 . Besides, the birnessite‐like Ca‐Mn(Ni)‐O catalyst is stabilized by coupling to NiMnO 3 nanoplate, thus forming a stable catalyst that can work for >500 h without attenuation. This work optimizes biomimetic structures by introducing new elements, which provides new insight into developing efficient biomimetic materials.