Rapid visible-light-driven Rose Bengal dye degradation over a hydrothermally assembled g-C3N4-MXene composite

The efficient removal of toxic organic dyes from wastewater remains a significant challenge in environmental remediation. In this study, a novel hydrothermally assembled g-C 3 N 4 -MXene (Ti 3 C 2 T x ) heterostructure is developed as an efficient visible-light-driven photocatalyst for the degradation of Rose Bengal dye. Unlike conventional physical mixing approaches, exfoliated g-C 3 N 4 and Ti 3 C 2 T x MXene were integrated through a controlled hydrothermal process to achieve strong interfacial coupling and uniform dispersion. Structural and morphological analyses confirm the successful formation of the heterostructure with intimate contact between g-C 3 N 4 layers and the conductive MXene framework. Optical investigations reveal enhanced visible-light absorption and pronounced photoluminescence quenching in the composite, indicating improved charge separation and suppressed electron-hole recombination. The photocatalytic performance was systematically evaluated under visible-light irradiation using Rose Bengal as a model pollutant. Compared to MXene and pristine g-C 3 N 4 , which require approximately 60 and 30 min, respectively, for complete dye degradation, the g-C 3 N 4 -MXene composite achieves rapid degradation within 20 min, demonstrating significantly enhanced reaction kinetics. The superior performance is attributed to synergistic interfacial charge transfer, MXene-mediated electron transport, and increased density of active sites. This work highlights the importance of interfacial engineering in g-C 3 N 4 -MXene systems and provides a promising strategy for designing high-performance photocatalysts for sustainable wastewater treatment.