Exploring the potential of MnWO4/MXene/carbon xerogel photocatalyst for photo efficient degradation of crystal violet

Abstract

Photocatalytic degradation under visible light offers a sustainable approach for removing organic pollutants from wastewater. In this study, MnWO₄, MXene, carbon xerogel, and their composites were synthesized through a simple and efficient method and evaluated for the photocatalytic degradation of crystal violet (CV) dye. Among them, the MnWO₄/MXene/carbon xerogel composite exhibited superior performance, achieving 95 % CV dye removal within 60 min under optimized conditions (25 mg catalyst dose, 10 ppm dye concentration, pH 12). Kinetic studies confirmed the enhanced degradation rate compared to the individual components. The improved activity was attributed to the formation of an S-scheme heterojunction between MnWO₄ and MXene, facilitating efficient charge separation and maintaining strong redox potentials. Hydroxyl radicals (^•OH) and superoxide radicals (^•O₂⁻) were identified as the main reactive species. Additionally, the composite demonstrated good stability and recyclability, retaining over 90 % efficiency after four cycles. These findings suggest that the MnWO₄/MXene/carbon xerogel composite is a promising, stable photocatalyst for practical environmental remediation applications.