Noble metal-free CoS2/g-C3N4 nanosheet composite photocatalysts for improved visible-light photocatalytic hydrogen production

Various of CoS 2 /g-C 3 N 4 nanosheet composites were fabricated through supramolecular self-assembly and copolymerization approaches. This fabrication entailed the incorporation of CoS 2 nanoparticles into ultra-thin layers of g-C 3 N 4 nanosheets. Demonstrating a significant boost, these composites achieved a 28-fold increase in the photocatalytic H 2 evolution from H 2 O with visible light response, without the aid of noble metal nanocrystalline co-catalysts. The enhanced CoS 2 /g-C 3 N 4 composite sustained approximately 92.4 % of its initial photocatalytic activity after four repeated uses. The planar structure of g-C 3 N 4 nanosheet amplifies its specific surface area, which improves access to catalytic sites and reduces the transport distance for photo-excited electrons and holes. Moreover, the close conjunction of CoS 2 nanoparticles and g-C 3 N 4 nanosheets establishes p-n heterojunctions, which promote swift charge separation and transfer at the material interface. Based on these characteristics, an initial model for the photocatalytic process has been proposed. With its remarkable photocatalytic performance and durability, the developed CoS 2 /g-C 3 N 4 composite presents substantial potential for solar-driven H 2 production.