Boosting interfacial charge transfer of 2D g-C3N4 by incorporating 0D Ag and 2D metallic NiCo2O4 as dual electron donor and acceptor co-catalysts for photocatalytic hydrogen evolution

Efficient light absorption and photoinduced electron transfer from the g-C₃N₄ (CN) continue to be an ongoing challenge in photocatalytic hydrogen production. Nanodimensional metallic cocatalysts can offer superior electron transport pathways, thereby augmenting photocatalytic activity. In our work metallic NiCo₂O₄ (NCO) acts as an electron acceptor cocatalyst in a 2D-2D Schottky junction with CN and 0D silver (Ag) functions as a hot electron donor via the localized surface plasmon resonance phenomenon. The novel Ag–CN–NCO nanocomposite was shown to boost visible light absorption while inhibiting charge carrier recombination through optical experiments. The Ag–CN–NCO nanocomposite demonstrated superior photocatalytic activity compared to CN loaded with a single cocatalyst, producing hydrogen at a rate of approximately 2320 μmol/g/h. Additionally, Ag–CN–NCO produced a lower overpotential and almost five times more photocurrent density than CN, as demonstrated by photoelectrochemical studies. This work highlights the development of a novel charge transfer pathway by combining two co-catalysts with different functions and their combined action on the photocatalytic hydrogen production process.