CuS/Ag2O nanoparticles on ultrathin g-C3N4 nanosheets to achieve high performance solar hydrogen evolution

Ternary heterostructures play a crucial role in improving the separation of charge carriers and fast surface reaction kinetics, which in turn helps in understanding the effective photocatalytic water splitting performance. Herein, CuS/Ag2O nanoparticles were presented on a graphitic carbon nitride (g-C3N4) surface to obtain CuS/Ag2O/g-C3N4 material using facile hydrothermal and precipitation methods. Structural and morphological studies confirmed the presence of ternary nanostructures comprising CuS, Ag2O, and g-C3N4 with nanoparticle and nanosheet morphologies. The as-synthesized CuS/Ag2O/g-C3N4 exhibited a remarkable photocatalytic H2 production of 1752 µmol.h-1.g-1cat, which is considerably superior than those of CuS and g-C3N4. The improved H2 production performance which is due to the effective interfacial CuS/Ag2O/g-C3N4 heterojunction interface and superior hole (h+) trapping capability of the CuS at the CuS/Ag2O/g-C3N4 interface. This can efficiently enhance the lifetime of photoexcited charge carriers and enhance the electron density for the production of H2. The optimum CuS/Ag2O/g-C3N4 heterostructure remained stable after 8 successive experimental cycles, although with a slight change in the H2 production rate. Therefore, this study offers a novel approach to exploit the efficacy through the synergetic effect of integrating CuS as the photocatalyst and Ag2O as the visible sensitizer, thus proposing a viable strategy of using earth-abundant material to enhance the conversion of solar energy to fuel.