Novel WS₂ /Fe_0.95 S_1.05 Hierarchical Nanosphere as a Highly Efficient Electrocatalyst for Hydrogen Evolution Reaction

Fe_0.95 S_1.05 with high reactivity and stability was incorporated into WS₂ nanosheets via a one-step solvothermal method for the first time. The resulted hybrid catalyst has much higher catalytic activity than WS₂ and Fe_0.95 S_1.05 alone, and the optimal WS₂ /Fe_0.95 S_1.05 hybrid catalyst was found by adjusting the feed ratio. The addition of Fe_0.95 S_1.05 was proven to be able to enhance the hydrogen evolution reaction (HER) activity of WS₂ , and vice versa. At the same time, it was found that the catalytic effect of the hybrid catalyst was the best when the feed ratio was W : Fe=2 : 1. In other words, we confirmed that there is a synergistic effect between W- and Fe-based sulfide hybrid catalysts, and validated that the reason for the improved HER performance is the strong interaction between the two in the middle sulfur. WS₂ /Fe_0.95 S_1.05 -2 hybrid catalyst leads to enhanced HER activity, which shows a low overpotential of ∼0.172 V at 10 mA cm^-2 , low Tafel slope of ∼53.47 mV/decade. This study supplies innovative synthesis of a highly active WS₂ /Fe_0.95 S_1.05 hybrid catalyst for HER.