Electronic engineering of CoSe/FeSe2 hollow nanospheres for efficient water oxidation

• Published in: Nanoscale Vol. 12; no. 18; pp. 10196 - 10204
• Main Authors: Zhang, Yi, Xu, Jie, Lin, Lv, Wang, Aiwu, Zhang, Baoshun, Ding, Yigang, Wang, Chundong
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 14.05.2020
• Subjects: Adsorption; Catalysts; Current density; Electrocatalysts; Electron transfer; Electronic engineering; Hybrid composites; Hydrogen production; Nanospheres; Noble metals; Optimization; Oxidation; Oxygen evolution reactions; Particulate composites; Valence band
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/d0nr01809k

First-row non-precious metal-based catalysts are widely studied and recognized as potential substitutes for precious metal-based catalysts in the oxygen evolution reaction (OER) for hydrogen generation but their application remains challenging. In this study, a unique class of Co–Fe selenide hollow nanospheres (CoSe@FeSe2) is well-designed through a facile hydrothermal method. The in situ formed hybrid composites possess numerous interfaces allowing partial electron transfer via O2− bridges to optimize the adsorption feature of the reaction intermediates, *OH, *O, and *OOH, on the catalysts. The collected surface valence band spectra evidence the optimization of the intermediate adsorption and active sites. The as-synthesized CoSe@FeSe2 exhibits excellent OER activity with a low overpotential of 281 mV to drive a current density of 10 mA cm−2 and a low Tafel slope of 34.3 mV dec−1 in an alkaline electrolyte. Additionally, the advanced catalyst also shows super stability with negligible current density decay after 12 h. This work presents a prototype for the fabrication of highly efficient electrocatalysts using an electronic engineering strategy.