Hollow Spherical Structure CoS_2−xSe_x for Electrocatalytic Hydrogen Evolution Reaction

Abstract

A series of CoS_2−xSe_x (x=0.05, 0.1, 0.2, 0.3, and 2) composite catalysts were synthesized on carbon fiber paper via the hydrothermal method with Se doping. By precisely controlling the reaction temperature and Se doping level, a hollow spherical catalyst structure composed of CoSSe was successfully synthesized, which exhibited exceptional activity for hydrogen evolution in acidic solutions. The influences of Se doping on the microstructure and catalytic mechanism of hydrogen evolution reaction (HER) of these composites were systematically investigated. The experimental results reveal that the hollow spherical sample displays an overpotential value of 143 mV along with a Tafel slope value of 69.8 mV·dec⁻¹ at a current density of 10 mA·cm⁻² in an acid aqueous solution. Furthermore, it demonstrates remarkable cycling stability after undergoing 3000 cycles. The comprehensive analysis indicates that Se doping optimizes the electronic structure and enhances conductivity, meanwhile the unique hollow spherical architecture increases active sites for HER and significantly improves overall electrocatalytic performance.

Keywords

hydrogen evolution reaction / electrocatalysis / cobalt chalcogenides / anion compound substitution / hollow spherical structure

RIGHTS & PERMISSIONS

Wuhan University of Technology and Springer-Verlag GmbH Germany, Part of Springer Nature