WS_(1−x) Se_x nanoparticles decorated three-dimensional graphene on nickel foam: A robust and highly efficient electrocatalyst for the hydrogen evolution reaction

To find an effective alternative to scarce, high-cost noble platinum (Pt) electrocatalyst for hydrogen evolution reaction (HER), researchers are pursuing inexpensive and highly efficient materials as an electrocatalyst for large scale practical application. Layered transition metal dichalcogenides (TMDCs) are promising candidates for durable HER catalysts due to their cost-effective, highly active edges and Earth-abundant elements to replace Pt electrocatalysts. Herein, we design an active, stable earth-abundant TMDCs based catalyst, WS_(1−x) Se_x nanoparticles-decorated onto a 3D porous graphene/Ni foam. The WS_(1−x) Se_x /graphene/NF catalyst exhibits fast hydrogen evolution kinetics with a moderate overpotential of ~−93 mV to drive a current density of 10 mA cm⁻², a small Tafel slope of ~51 mV dec⁻¹, and a long cycling lifespan more than 20 h in 0.5 M sulfuric acid, which is much better than WS₂ /NF and WS₂ /graphene/NF catalysts. Our outcomes enabled a way to utilize the TMDCs decorated graphene and precious-metal-free electrocatalyst as mechanically robust and electrically conductive catalyst materials.