Promoting Formation of Oxygen Vacancies in Two-Dimensional Cobalt-Doped Ceria Nanosheets for Efficient Hydrogen Evolution

• Published in: Journal of the American Chemical Society Vol. 142; no. 14; pp. 6461 - 6466
• Main Authors: Jiang, Shuaihu, Zhang, Ruya, Liu, Hongxian, Rao, Yuan, Yu, Yanan, Chen, Shan, Yue, Qin, Zhang, Yanning, Kang, Yijin
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08.04.2020
• Subjects: catalysts; catalytic activity; cobalt; dissociation; energy; fossil fuels; hydrogen; hydrogen production; nanosheets; oxygen; thermal degradation
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.9b13915

As an alternative for depleting fossil fuel energy, hydrogen economy desires low-cost and efficient hydrogen production from water splitting. In order to explore a cheap, abundant, active, and durable catalyst for the electrocatalytic hydrogen evolution reaction (HER), two-dimensional (2D) ceria nanosheets are produced through a thermal decomposition exfoliation method from CeCO3OH with a layer-stacked structure. The additional cobalt dopant promotes formation of oxygen vacancies in ceria nanosheets and, in turn, optimizes hydrogen binding/water dissociation and increases the active sites. As a result, the 2D Co-doped CeO2 nanosheets exhibit an excellent catalytic performance in alkaline HER such that the overpotential is as low as 132 and 215 mV to deliver a high current density of 100 and 500 mA cm–2, respectively, outperforming Pt. Such 2D Co-doped CeO2 nanosheets are also durable HER electrocatalysts, as the activity loss during an extended period of operation is nearly negligible.