Interfacial effects of a ternary heterostructure on 1 T/2H MoS2 for Pt/C-comparable alkaline hydrogen evolution at industrially relevant high current densities

The development of efficient and cost-effective electrocatalysts for hydrogen production is crucial for advancing a carbon-neutral circular economy. The hydrogen evolution reaction (HER) performance of MoS 2 in alkaline media is hindered by its sluggish water-dissociation kinetics and inert basal planes. Herein, we report a novel ternary heterostructure, consisting of γ-FeOOH nanosheets and smaller Ni 3 S 2 nanosheets grown on vertical 1 T/2H MoS 2 nanosheets, that exhibits enhanced HER activity. Systematic investigations suggest that the enhanced HER performance is associated with the interfacial interactions among Ni 3 S 2 , γ-FeOOH, and MoS 2 , which involve strain coupling, electronic coupling, and functional synergy. Accordingly, the Ni 3 S 2 /γ-FeOOH/MoS 2 /CC electrode requires overpotentials of only 99.6 and 176.1 mV at 10 and 100 mAcm −2 , respectively. Remarkably, it outperforms commercial Pt/C at current densities exceeding 173.2mA cm −2 and requires an overpotential of only 213.9mV at 300 mA cm −2 , while also exhibiting robust operational stability at high current densities, highlighting its promise for further exploration toward practical alkaline water electrolysis systems. This work provides a promising strategy for designing high-performance, earth-abundant MoS 2 -based HER catalysts for alkaline water electrolysis.