Designing multi-heterogeneous interfaces of Ni-MoS₂@NiS₂@Ni₃S₂ hybrid for hydrogen evolution

The transition metal chalcogenides represented by MoS₂ are the ideal choice for non-precious metal-based hydrogen evolution catalysts. However, whether in acidic or alkaline environments, the catalytic activity of pure MoS₂ is still difficult to compete with Pt. Recent studies have shown that the electronic structure of materials can be adjusted by constructing lattice-matched heterojunctions, thus optimizing the adsorption free energy of intermediates in the catalytic hydrogen production process of materials, so as to effectively improve the electrocatalytic hydrogen production activity of catalysts. However, it is still a great challenge to prepare heterojunctions with lattice-matched structures as efficient electrocatalytic hydrogen production catalysts. Herein, we developed a one-step hydrothermal method to construct Ni-MoS₂@NiS₂@Ni₃S₂ (Ni-MoS₂ on behalf of Ni doping MoS₂) electrocatalyst with multiple heterogeneous interfaces which possesses rich catalytic reaction sites. The Ni-MoS₂@NiS₂@Ni₃S₂ electrocatalyst produced an extremely low overpotential of 69.4 mV with 10 mA·cm⁻² current density for hydrogen evolution reaction (HER) in 1.0 M KOH. This work provides valuable enlightenment for exploring the mechanism of HER enhancement to optimize the surface electronic structure of MoS₂, and provides an effective idea for constructing rare metal catalysts in HER and other fields.