Tuning the Catalytic Activity of MoS2−x−NbSx Heterostructure Nanosheets for Bifunctional Acidic Water Splitting

Developing durable electrocatalysts with high activity for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in acidic media is critically important for clean power production. In this study, MoS_2−x−NbS_x heterostructure nanosheets are synthesized from a solid-state reaction method followed by liquid phase exfoliation, and their catalytic performance is optimized. The MoS_2−x−NbS_x heterostructure nanosheets with optimal precursors ratio exhibit promising attributes for applications in the HER and OER compared to pristine MoS₂ and Nb under the same conditions. The MoS_2−x−NbS_x heterostructure nanosheets catalyst on glassy carbon electrodes shows the minimum overpotential of 159 mV for HER and 295 mV for OER at a current density of 10 mA cm⁻² in 0.5 m H₂SO₄. This research offers valuable insights into the fabrication of heterostructure nanosheets and evaluates their potential as effective electrocatalysts for water splitting compared with pristine 2D materials in an acid environment.