A potential-driven switch of activity promotion mode for the oxygen evolution reaction at Co3O4/NiOxHy interface

• Published in: eScience (Beijing) Vol. 2; no. 4; pp. 438 - 444
• Main Authors: Wang, Wang, Wang, Zixu, Hu, Youcheng, Liu, Yucheng, Chen, Shengli
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2022; KeAi Communications Co. Ltd
• Subjects: Double exchange interaction; Energetic span; Interface engineering; Oxygen evolution reaction; Potential-driven switch of mechanism; Interface engineering; Potential-driven switch of mechanism; Oxygen evolution reaction; Energetic span; Double exchange interaction
• ISSN: 2667-1417; 2667-1417
• DOI: 10.1016/j.esci.2022.04.004

Co3O4 spinel oxides have manifested promising activity toward the oxygen evolution reaction (OER) through effective modifications. For them to become top electrocatalysts, however, accurate accounts of the catalytic kinetics are essential to gain a deep understanding of the activity promotion mechanisms. Herein, we use a newly proposed kinetic model based on energetic span as the rate-determining term for the electrocatalytic reaction to throw light on the promotion mechanism of Co3O4 interfaced with nickel hydroxides (NiOxHy) for the OER. We find that depending on the electrode potential, the OER kinetics at the designed interface between Co3O4 and NiOxHy are boosted in entirely different ways. As a result, the OER can occur at a lower onset potential as well as a low Tafel slope. This work emphasizes the benefit of using rational theoretical models for electrocatalyst design. [Display omitted] •Proposed a newly energetic span-based kinetic model instead of the commonly used ΔGmax -based model.•A potential-driven switch in the promotion mode for the OER at the interface was elucidated.•The catalyst eludes the thermodynamic limitation caused by the linear scaling relation.