Copper-Copper Oxide Heterostructural Nanocrystals Anchored on g-C3N4 Nanosheets for Efficient Visible-Light-Driven Photo-Fenton-like Catalysis

Abstract

The development of efficient and sustainable photocatalysts for wastewater treatment remains a critical challenge in environmental remediation. In this study, a ternary photocatalyst, Cu-Cu2O/g-C3N4, was synthesized by embedding copper-copper oxide heterostructural nanocrystals onto g-C3N4 nanosheets via a simple deposition method. Structural and optical characterization confirmed the successful formation of the heterostructure, which combines the narrow bandgap of Cu2O, the high stability of g-C3N4, and the surface plasmon resonance (SPR) effect of Cu nanoparticles. The photocatalytic performance was evaluated through the degradation of Rhodamine B (RhB) in a photo-Fenton-like reaction system under visible light irradiation. Among the catalysts tested, the 30 wt% Cu-Cu2O/g-C3N4 composite exhibited the highest catalytic efficiency, achieving a reaction rate constant approximately 3 times and 1.5 times higher than those of Cu-Cu2O and g-C3N4, respectively. Mechanistic studies suggest that the heterostructure facilitates efficient charge separation and promotes the reduction of Cu2+ to Cu+, thereby enhancing ∙OH radical generation. The catalyst also demonstrated excellent stability and reusability across a wide pH range. These findings provide a new strategy for designing highly efficient photocatalysts for organic pollutant degradation, contributing to the advancement of advanced oxidation processes for environmental applications.