Inducing Intermolecular Oxygen Coupling by Introducing S and FeOOH on Co(OH)2 Nanoneedle Arrays for Industrial Water Oxidation

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-11, Vol.20 (46), p.e2405080-n/a
• Main Authors: Zhang, Yijie, Zhang, Weiyi, Zhang, Xiaowen, Gao, Yuan, Zhao, Qiang, Li, Jinping, Liu, Guang
• Format: Article
• Language: English
• Subjects: anion exchange membrane water electrolyzer; Anion exchanging; Arrays; Charge transfer; Cobalt; Commercialization; Coupling; Electrocatalysts; Electrolysis; Electron transfer; heterogeneous interfaces; Heterostructures; Hydrogen production; Industrial water; Iron; lattice oxygen activation; Oxidation; oxygen evolution reaction; Oxygen evolution reactions; water splitting
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202405080

The design of electrocatalysts for oxygen evolution reaction (OER) remains a limitation of industrial hydrogen production by electrolysis of water. Excellent and stable OER catalysts can be developed by activating lattice oxygen and changing the reaction path. Herein, S and FeOOH on the Co(OH)2 nanoneedle arrays are introduced to construct a heterostructure (S‐FeOOH/Co(OH)2/NF) as a proof of concept. Theoretical calculations and experimental suggest that the Co‐O‐Fe motif formed at the heterogeneous interface with the introduction of FeOOH, inducing electron transfer from Co to Fe, enhancing Co─O covalency and reducing intramolecular charge transfer energy, thereby stimulating direct intramolecular lattice oxygen coupling. Doping of S in FeOOH further accelerates electron transfer, improves lattice oxygen activity, and prevents dissolution of FeOOH. Consequently, the overpotential of S‐FeOOH/Co(OH)2/NF is only 199 mV at 10 mA cm−2, and coupled with the Pt/C electrode can be up to 1 A cm−2 under 1.79 V and remain stable for over 120 h in an anion exchange membrane water electrolyzer (AEMWE). This work proposes a strategy for the design of efficient and stable electrocatalysts for industrial water electrolysis and promotes the commercialization of AEMWE. The introduction of S and FeOOH into the Co(OH)2 nanoneedle array can induce the upshift of the O 2p band and the downshift of the metal 3d band, thereby improving the M─O covalent and activating the lattice oxygen, inducing direct intramolecular oxygen coupling, thereby exhibiting excellent OER activity and stability.