Confinement synergy at the heterointerface for enhanced oxygen evolution
Dongdi Wang, Shanshan Ruan, Peiyu Ma, Ruyang Wang, Xilan Ding, Ming J. Zuo, Lidong Zhang, Zhirong Zhang, Jie Zeng, Jun Bao
Abstract
Two-dimensional transition metal hydroxides with abundant reserves and low prices have played an indispensable role in energy catalytic applications. Recent reports indicated that the incorporation of Fe species into Co-based catalysts can synergistically enhance oxygen evolution reaction (OER) activity. Constructing a heterointerface on the surface of Co-based catalysts can provide a platform to investigate the role of heterointerface in reaction kinetics. Herein, we constructed a Fe-O-Co heterointerface without electronic effect by depositing FeO x clusters on the oxygen vacancies of CoOOH surface. FeO x /CoOOH exhibited excellent OER intrinsic activity, which can deliver the turnover frequency (TOF) of 4.56 s − 1 at the overpotentials of 300 mV and the Tafel slope of 33 mV×dec −1 . In-situ electrochemical impedance spectroscopy (EIS) and density functional theory (DFT) calculations demonstrated that the synergistic effect between Fe sites and Co sites confined at the Fe-O-Co heterointerface accelerated the charge transfer during OER and optimized the adsorption of oxygen intermediates, consequently enhancing OER.