Dual-cation doping precisely reducing the energy barrier of the rate-determining step for promoting oxygen-evolving activity. Issue 7 (7th March 2023)

• Record Type: Journal Article
• Authors: Xu, Hui; Wang, Cheng; Huang, Bingji; Shang, Hongyuan; Du, Yukou
• Is Part Of: Inorganic chemistry frontiers. Volume 10:Issue 7(2023)
• Page Start: 2067
• Page End: 2074
• Publication Date: 2023-03-07
• Subjects: Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d3qi00138e
• Languages: English
• ISSNs: 2052-1553

Abstract

Abstract : A sunflower-like Ir, Fe-codoped Co(OH)2 catalyst assembled by nanosheets is designed for boosting electrocatalytic OER, where dual-cation doping can significantly decrease the energy barrier of the rate-determining step for OER. Abstract : The energy barrier for the rate-determining step (RDS) is exceptionally critical for the catalytic oxygen evolution reaction (OER) efficiency of an electrocatalyst; however, facilely decreasing the energy barrier of RDS and realizing the precise manipulation of the reaction process remains challenging. Herein, through constructing a nanosheet assembled sunflower-like Co(OH)2 with Ir, Fe codoping, the electronic structure and binding strengths with oxygen-involved intermediates of Co active sites are considerably moderated. First-principles calculations and comprehensive characterizations suggest that Fe and Ir codoping significantly lowers the electrochemical reaction barrier and promotes the OER reaction kinetics by precisely accelerating the formation process of *O. Moreover, the nanosheet-assembled open architectures enable the catalyst with plentiful catalytically active sites and facilitate mass transport and electron transfer. As a result, the optimal electrocatalyst can exhibit outstanding oxygen-evolving activity with an ultralow overpotential of 254 mV at 10 mA cm −2 . This study realizes the precise manipulation of the reaction energy barrier of OER via Ir, Fe dual doping, which will be a generic paradigm for designing advanced yet cost-effective electrocatalysts.