An effective pre-catalytic electrode based on iron/nickel hydroxyquinoline for water oxidation

• Published in: Surfaces and interfaces 2022-10, Vol.33, p.102153, Article 102153
• Main Authors: Wang, Weiqi, Chen, Peng, Chen, Xin, Zhou, Hongbo, Fu, Xiaoqi, Liu, Jiale, Liu, Yuanjun, Cheng, Xiaofang, Song, Xiaojie, Zhu, Guoxing
• Format: Article
• Language: English
• Subjects: Catalytic electrode; Hydroxyquinoline salts; Metal-organic framework; Oxygen evolution reaction; Water oxidation
• ISSN: 2468-0230; 2468-0230
• DOI: 10.1016/j.surfin.2022.102153

•Iron/nickel hydroxyquinoline salts were generated on nickel foam as pre-catalytic electrodes.•The pre-catalytic electrodes can be activated during electrochemical test process.•With an overpotential of 293 mV, the electrode can provide 50 mA cm−2 of current density.•The surface layer evolves into metal oxyhydroxides acting as the catalytic active phase. Oxygen evolution reaction is related in various energy-related devices including water splitting and metal-air batteries. Herein, the reaction between Fe3+, Ni2+, and 8-hydroxyquinoline was used to generate iron/nickel hydroxyquinoline salts (FeNi-HQ), which were loaded on a nickel framework for water oxidation. The formed coordination compound contains iron/nickel bimetal sites that show strong interaction between them, and so presents excellent electrocatalytic activity for oxygen evolution after an electrochemical activation process. Driven by a small overpotential of 293 mV, the activated catalytic electrode can provide 50 mA cm−2 of current density with higher stability. Investigation on the catalyst after long time catalytic operation confirms that the surface layer is activated with the formation of metal oxyhydroxides. This study provides a new and effective pre-catalytic electrode for oxygen evolution. [Display omitted]