Snowflake-like Mo-doped Ni9S8@NiS/Ni-Net heterostructure self-supporting electrode for alkaline hydrogen evolution reaction at large current density

The design of hierarchical heterostructured catalysts is a crucial strategy for enabling efficient and stable industrial-scale hydrogen production. In this paper, a hierarchical Mo-doped Ni 9 S 8 @NiS self-supporting electrode (Mo-Ni 9 S 8 @NiS/Ni-Net) was successfully synthesized on Ni-Net by a simple one-step solvothermal method, which is a snowflake-like structure composed of nanorods and composite nanoparticles. Owing to its excellent conductivity, abundant active sites and strong interaction between heterogeneous interfaces, Mo-Ni 9 S 8 @NiS/Ni-Net exhibits excellent catalytic activity (100 mA/cm 2 @181 mV, 1000 mA/cm 2 @393 mV) and stability (70 mA/cm 2 @500 h) for hydrogen evolution reaction (HER) in 1 M KOH solution. More importantly, the overpotential of Mo-Ni 9 S 8 @NiS/Ni-Net (1000 mA/cm 2 @373 mV) is lower than that of Raney Ni electrode (1000 mA/cm 2 @399 mV) used in industry under simulated working conditions (6 M KOH solution). This study provides a promising option for developing an economical and efficient non-noble metal-based hydrogen evolution reaction electrode.