Se-Doping Activates FeOOH for Cost-Effective and Efficient Electrochemical Water Oxidation

• Published in: Journal of the American Chemical Society Vol. 141; no. 17; pp. 7005 - 7013
• Main Authors: Niu, Shuai, Jiang, Wen-Jie, Wei, Zengxi, Tang, Tang, Ma, Jianmin, Hu, Jin-Song, Wan, Li-Jun
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 01.05.2019
• Subjects: catalysts; cobalt; cost effectiveness; electrochemistry; electrodes; hydrogen production; iron; iron oxyhydroxides; nickel; oxidation; oxygen production
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.9b01214

Ni or Co is commonly required in efficient electrocatalysts for oxygen evolution reaction (OER). Although Fe is much more abundant and cheaper, full-Fe or Fe-rich catalysts suffer from insufficient activity. Herein, we discover that Se-doping can drastically promote OER on FeOOH and develop a facile on-site electrochemical activation strategy for achieving such a Se-doped FeOOH electrode via an FeSe precatalyst. Theoretical analysis and systematic experiments prove that Se-doping enables FeOOH as an efficient and low-cost OER electrocatalyst. By optimizing the electrode structure, an industrial-level OER current output of 500 mA cm–2 is secured at a low overpotential of 348 mV. The application of such an Fe-rich OER electrode in a practical solar-driven water splitting system demonstrates a high and stable solar-to-hydrogen efficiency of 18.55%, making the strategy promising for exploring new cost-effective and highly active electrocatalysts for clean hydrogen production.