Amorphous MoS₂ Decorated Ni₃S₂ with a Core-shell Structure of Urchin-Like on Nickel-Foam Efficient Hydrogen Evolution in Acidic and Alkaline Media

The large-scale commercialization of the hydrogen evolution reaction (HER) necessitates the development of cost-effective and highly efficient electrocatalysts. Although transition metal sulfides, such as MoS2 and Ni3S2, hold great potential in the field of HER, their catalytic performance has been unsatisfactory due to incomplete exposure of active sites and poor electrical conductivity. In this work, via a simple hydrothermal strategy, amorphous MoS2 nanoshells in the form of urchin-like MoS2-Ni3S2 core-shell heterogeneous structure is realized and in situ loaded on nickel foam (A-MoS2-Ni3S2-NF). In particular, XPS analysis results show that the coupling of amorphous MoS2 and Ni3S2 makes the electrode surface exhibit electron-abundant property, which will have a positive impact on HER catalytic activity. In addition, the fully exposed active site of amorphous MoS2 is another crucial factor contributing to its high catalytic performance of A-MoS2-Ni3S2-NF electrode. In particular, at a current density of 10 mA cm(-2), the overpotential of electrode is 95 mV (1.0 m KOH) and 145 mV (0.5 m H2SO4). This work highlights the importance of amorphous MoS2 and MoS2-Ni3S2 of sea-urchin core-shell structure in optimizing HER performance, which provides an important reference for HER research.