Electrochemically induced in-situ surface self-reconstruction on Ni, Fe, Zn ternary-metal hydroxides towards the oxygen-evolution performance

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 410; p. 128331
• Main Authors: Meng, Tian, Li, Qun, Yan, Mengxia, Wang, Dewen, Fan, Libing, Liu, Xiaojuan, Xing, Zhicai, Yang, Xiurong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.04.2021
• Subjects: Electronic structure modulation; Oxygen evolution reaction; Surface self-reconstruction; Ternary metal hydroxides; Ternary metal hydroxides; Electronic structure modulation; Surface self-reconstruction; Oxygen evolution reaction
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2020.128331

We synthesize Ni, Fe, Zn ternary hydroxides (NFZ-TH) and reveal the in-situ self-reconstruction process of NFZ-TH under OER overpotential. NFZ-TH derived materials (NFZ-TH-SR) after self-reconstruction exhibits superior OER catalytic performance and stable long term electrolysis performance. Ni at nearest-neighbour defect-site and defect-/corner- sited Fe with high OER activity are investigated by In-situ Raman spectra and DFT calculations. [Display omitted] •An in-situ surface self-reconstruction of NFZ-TH during OER process is found.•NFZ-TH-SR deliver a small overpotential of 217 mV at 10 mA cm−2 towards OER.•Vacancy defects boost the activity of both Ni and Fe at specific sites. Self-reconstruction of oxygen evolution reaction (OER) catalyst, especially metal (oxy)hydroxides or oxides, has attracted much attention. Herein, an in-situ self-reconstruction process for Ni, Fe, Zn ternary-metal hydroxides (NFZ-TH) involving significant morphology transformation, and self-modulated electronic structure change of Ni and Fe owing to the etching of Zn species under anodic polarization potential is revealed. NFZ-TH derived materials, undergoing in-situ self-reconstruction (NFZ-TH-SR), exhibits superior OER performance (η = 217 mV @j = 10 mA cm−2geometry) and excellent stability over a period of ~48 h. Nano-pitted surface resulting from etching of Zn species improves the electrochemical surface area. Meanwhile, in NFZ-TH-SR, large amounts of defects induced defect-/corner-sited Fe and adjustability of NiOOH species are verified by Mössbauer spectra and in-situ Raman spectra respectively. Density functional theory calculations give insight that both defect-/corner- sited Fe and Ni at next-nearest-neighbour defect-site have high activity. This paper helps understand that the proposed in-situ self-reconstruction strategy can improve the electrochemical performance of OER catalysts.