One-step sintering synthesis of a robust self-supported MoSe ₂ /Ni ₃ Se ₂ heterostructure electrode for efficient hydrogen evolution at a high current density

It is crucial to develop efficient and stable hydrogen evolution reaction (HER) electrocatalysts to facilitate sustainable hydrogen production. Yet, the high price and poor stability of noble metal-based catalysts at high-current densities hinder the industrial application of the HER. In this study, a MoSe₂/Ni₃Se₂ heterostructure self-supported electrode featuring a crosslinked network of MoSe₂ sheets and Ni₃Se₂ particles was successfully synthesized via an innovative one-step sintering process. The optimized MoSe₂/Ni₃Se₂-800 self-supported electrode, characterized by its well-defined heterostructure, abundant active sites, and robust interfacial bonding, exhibits superior catalytic performance and stability. The MoSe₂/Ni₃Se₂-800 self-supported electrode exhibits a remarkably low overpotential of just 341 mV under 1000 mA cm^-2. Furthermore, the electrode can operate for 200 h under approximately 800 mA cm^-2. This study highlights the potential industrial application of the sintered MoSe₂/Ni₃Se₂ heterostructure self-supported electrode and introduces a novel strategy for designing and optimizing other self-supported transition metal chalcogenide heterostructure electrodes as well.