Dual-metal co-catalyst integrated graphitic carbon nitride for photocatalytic hydrogen evolution reactionGupta, Suraj (Avtor) Batool, Samar (Avtor) Maček, Marjeta (Avtor) Daneu, Nina (Avtor) Johny, Joyal (Avtor) Spreitzer, Matjaž (Avtor) Cherevan, Alexey (Avtor) hydrogen evolution reactionnanosheetsGraphitic carbon nitride (g-C3N4) nanosheets are extensively used in photocatalytic applications but are often decorated with noble-metal co-catalysts to yield relevant efficiencies. Herein, we report a dual-metal co-catalyst system comprising cobalt and molybdenum (CoMo) nanoclusters uniformly integrated into heptazine g-C3N4 nanosheets for enhanced visible-light-driven hydrogen evolution reaction (HER). The intimate contact between metals as well as with gC3N4 layer was verified through X-ray absorption and X-ray photoelectron spectroscopies. Mechanistic insights obtained through a combination of experimental and computational studies suggest that Co acts as primary catalytic center, while Mo plays a preliminary role in facilitating surface hydrogen coverage, collectively accelerating the redox rates and achieving 10 times higher performance compared to bare gC3N4. Post-HER analysis reveals disintegration of co-catalyst into Co single-atoms, which then takes the leading role in sustaining the HER. The role of co-catalyst was mainly limited to the surface, acting as electron trap, reducing charge recombination and as a HER catalytic center. The composite exhibits excellent photostability over 13 h of ON/OFF illumination cycles, highlighting its potential for intermittent operations under practical conditions. This study presents a co-catalyst design strategy leveraging dual-metal synergy as a non-noble, scalable alternative to conventional noble-metal-based HER co-catalysts for solar fuel generation.Elsevier20272026-06-30 10:43:31Neznano30621Nizozemskasl© 2026 The Author(s).