Temperature-Induced Structure Transformation from Co0.85Se to Orthorhombic Phase CoSe2 Realizing Enhanced Hydrogen Evolution Catalysis

Jing Bai; Yechen Wang; Yange Wang; Tiantian Zhang; Gang Dong; Dongsheng Geng; Dongjie Zhao

doi:10.1021/acsomega.2c01020

Temperature-Induced Structure Transformation from Co_0.85Se to Orthorhombic Phase CoSe₂ Realizing Enhanced Hydrogen Evolution Catalysis

ACS Omega. 2022 Apr 28;7(18):15901-15908. doi: 10.1021/acsomega.2c01020. eCollection 2022 May 10.

Authors

Jing Bai^{1

2}, Yechen Wang¹, Yange Wang¹, Tiantian Zhang¹, Gang Dong¹, Dongsheng Geng¹, Dongjie Zhao³

Affiliations

¹ Beijing Advanced Innovation Center for Materials Genome Engineering, School of Material Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China.
² Shunde Graduate School, University of Science and Technology Beijing, Foshan 528000, People's Republic of China.
³ Institute for Future, School of Automation, Qingdao University, Qingdao 266071, People's Republic of China.

Abstract

Transition-metal chalcogenides (TMC) have been widely studied as active electrocatalysts toward the hydrogen evolution reaction due to their suitable d-electron configuration and relatively high electrical conductivity. Herein, we develop a feasible method to synthesize an orthorhombic phase of CoSe₂ (o-CoSe₂) from the regeneration of Co_0.85Se, where the temperature plays a key role in controlling the structure transformation. To the best of our knowledge, this is the first report about this synthetic route for o-CoSe₂. The resulting o-CoSe₂ catalysts exhibit enhanced hydrogen evolution reaction performance with an overpotential of 220 mV to reach 10 mA cm^-2 in 1.0 M KOH. Density functional theory calculations further reveal that the change in the Gibbs free energy of hydrogen, water adsorption energy, and the downshifted d-band center make o-CoSe₂ more suitable for accelerating the HER process.