Synergistic balancing hydrogen and hydroxyl adsorption/desorption of nickel sulfide via cation and anion dual-doping for boosting alkaline hydrogen evolution

Balancing hydrogen (Hads) and hydroxyl (OHads) adsorption/desorption plays a pivotal role to accelerate the sluggish alkaline hydrogen evolution reaction (HER) kinetics. Unfortunately, the adsorption energies for Hads and OHads can hardly be optimized simultaneously due to the lack of matched active sites for Hads and OHads. Herein, cation and anion codoping is used to construct Co and B doped Ni3S4 (Co-B-Ni3S4) with dual active sites to synergistically near-optimal adsorption energies for Hads and OHads concurrently. The obtained catalyst exhibits a superior HER performance with a tiny overpotential of 35 mV to obtain current density 10 mA cm−2 and a low Tafel slope of 52 mV dec-1, even outperforms Pt/C at high current density. The related microkinetics analysis and density functional theory confirm that the B doping can elevate d-band center to facilitates the water dissociation, Co doping endows the appropriate Had adsorption energies to accelerate generation and release for H2. This work points out a venue for kinetic-oriented design of alkaline HER and beyond at the atomic level.