Synthesis of MoS2/CoSe2-x hybrids as electrocatalysts for hydrogen evolution reaction

For the first time, novel electrocatalysts MoS2/CoSe2-x (x are the weight ratio of MoS2/CoSe2, x = 15%, 25%, 35%) have been synthesized by solvothermal method, which are facile, low-cost, and easy to realize scalable production. While the results of electrochemical testings show that composition can improve the properties, the ratio of hybrids can effect the catalytic performances. And when the x is 25% (MoS2/CoSe2-25), the hybrid shows the best catalytic performances towards hydrogen evolution reaction (HER), with a low overpotential of 113 mV at 10 mA/cm2, the smaller Tafel slope (45 mV/dec), and kinetic resistance (23 Ω), and the current density can be maintained for at least 24 h. Thus, MoS2/CoSe2-25 shows potential application in water splitting.