CoMoS@TiO2 Heterostructures as Hydrogen Evolution Catalyst for Alkaline Water Electrolysis

Hydrogen production through water electrolysis emerges as the most viable method, holding strategic significance for achieving sustainable development at national and societal levels. In this work, CoMoS@TiO2 heterostructures were prepared via the hydrothermal method and thermal vulcanization on Ti substrate, where CoMoS nanosheets were vertically grown on TiO2 nanobelt arrays. The CoMoS@TiO2 heterostructures were tested as hydrogen evolution electrocatalyst in 1 M KOH, with the optimal overpotential of 112 mV at a current density of 10 mA cm–2 and merely 5% activity degradation after 100 h stability testing. The enhanced HER activity originates from synergistic effects: (i) TiO2 nanobelt arrays offer abundant anchoring sites and excellent alkaline stability; (ii) rich heterojunction interfaces between CoMoS nanosheets and TiO2 nanobelts maximize active site exposure; (iii) improved conductivity enabled by CoMoS enhances charge transfer.