Surface anion-rich NiS2 hollow microspheres derived from metal–organic frameworks as a robust electrocatalyst for the hydrogen evolution reaction

Abstract

Exploring highly efficient and low cost electrocatalysts for the hydrogen evolution reaction (HER) remains a significant challenge in the renewable energy area. In this study, we report a novel metal–organic framework (MOF)-engaged microwave sulfurization strategy to synthesize pyrite-structured nickel disulfide microspheres (NiS₂ HMSs) with a well-defined hollow morphology and surface anion modification. The resulting NiS₂ HMSs exhibit excellent performance for electrocatalyzing the HER with expected activity and durability. The optimized NiS₂ HMSs need only 219 mV to offer a current density of 10 mA cm⁻² for the HER in alkaline medium, and compare favorably to previously reported Ni-based nonprecious electrocatalysts and even outperform most of the nickel sulfide-based electrocatalysts. This work will open a new avenue for the preparation of various surface anion-rich metal sulfides from the corresponding MOFs for electrocatalytic water splitting.