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Constructing an Adaptive Heterojunction as a Highly Active Catalyst for the Oxygen Evolution Reaction |
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| Authors: | Xiao Ren Chao Wei Yuanmiao Sun Xiaozhi Liu Fanqi Meng Xiaoxia Meng Shengnan Sun Shibo Xi Yonghua Du Zhuanfang Bi Guangyi Shang Adrian C. Fisher Lin Gu Zhichuan J. Xu |
| Affiliation: | 1. School of Material Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798 Singapore;2. School of Material Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798 Singapore The Cambridge Centre for Advanced Research and Education in Singapore, 1 CREATE Way, Singapore, 138602 Singapore;3. Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, P.O. Box 603, Beijing, 100190 China;4. Department of Applied Physics, Key Laboratory of Micro-Nano Measurement-Manipulation and Physics (Ministry of Education), Beihang University, Beijing, 100191 China;5. Institute of Chemical and Engineering Sciences, A*STAR 1 Pesek Road, Singapore, 627833 Singapore;6. The Cambridge Centre for Advanced Research and Education in Singapore, 1 CREATE Way, Singapore, 138602 Singapore Department of Chemical Engineering, University of Cambridge, Cambridge, CB2 3RA UK |
| Abstract: | Electrochemical water splitting is of prime importance to green energy technology. Particularly, the reaction at the anode side, namely the oxygen evolution reaction (OER), requires a high overpotential associated with O O bond formation, which dominates the energy-efficiency of the whole process. Activating the anionic redox chemistry of oxygen in metal oxides, which involves the formation of superoxo/peroxo-like (O2)n−, commonly occurs in most highly active catalysts during the OER process. In this study, a highly active catalyst is designed: electrochemically delithiated LiNiO2, which facilitates the formation of superoxo/peroxo-like (O2)n− species, i.e., NiOO*, for enhancing OER activity. The OER-induced surface reconstruction builds an adaptive heterojunction, where NiOOH grows on delithiated LiNiO2 (delithiated-LiNiO2/NiOOH). At this junction, the lithium vacancies within the delithiated LiNiO2 optimize the electronic structure of the surface NiOOH to form stable NiOO* species, which enables better OER activity. This finding provides new insight for designing highly active catalysts with stable superoxo-like/peroxo-like (O2)n− for water oxidation. |
| Keywords: | adaptive junctions cycling delithiation oxygen evolution reconstruction |