Enhancing solar-driven overall water splitting via both sacrifice and noble metal free photocatalysis: copper cluster/boron-doped carbon nitride catalysts.

The major impediment to the additional industrialization of water splitting is the high cost of the co-catalyst made of noble metals and the sacrificial reagent. A binary photocatalytic system, consisting of B-doped g-C₃N₄ nanosheets (Cu₂₀@BCN-X) and atomically accurate copper clusters, is designed in this study. The copper clusters serve as co-catalysts for H₂ evolution and exhibit Pt-like activity, whereas the nanosheets serve as carriers and semiconductor components for O₂ evolution. Such binary system, created using simple techniques, demonstrates hydrogen bonding interactions that promote synergistic effects and efficient binding and charge transfer across the interface between the two components. Band position manipulation of carbon nitride nanosheets demonstrates a Z-scheme charge transfer mechanism between the nanosheets and copper clusters. This photocatalytic system can accomplish the photocatalytic overall water splitting process (259.9 µmol g⁻¹ h⁻¹ of H₂ and 129.4 µmol g⁻¹ h⁻¹ of O₂) without using sacrificial agents or noble metal co-catalysts. This work lays the foundation for the design of overall water splitting catalysts by precisely manipulating the energy levels, and it also paves the way for commercialized photocatalytic catalysts that do not require noble metals or sacrificial chemicals. [ABSTRACT FROM AUTHOR]