Rapid photocatalytic degradation of Industrial dyes and investigation on toxicological effect of the treated water using copper incorporated tungsten oxide nanoparticles

Abstract

Environmental pollution has been perceived as one of the serious issues of the modern world. Textile effluents are especially of concern because they colour the drains and diminish the water quality. Herein, high crystalline Cu-doped WO₃ nanoparticles were prepared using a facile chemical method. This study explores the impact of copper ions incorporated into WO₃ to enhance the photocatalytic breakdown rate of textile effluent. Structural, morphology, and optical properties were studied using advanced instruments. The formation of a monoclinic WO₃ phase in all synthesized samples was confirmed through X-ray diffraction (XRD) analysis. Optical studies revealed that Cu-doped WO₃ nanoparticles exhibit a narrowed bandgap energy, facilitating the generation of free radicals capable of effectively degrading textile effluent dye molecules. Under natural sunlight, the Cu-doped WO₃ demonstrated exceptional photocatalytic efficiency, achieving 96.1 % degradation of Rhodamine 6G (RG) and 91.7 % degradation of Methylene Blue (MB) within 2 h. The incorporation of Cu dopants provided an efficient pathway for electron excitation from the valence to the conduction band, resulting in enhanced photocatalytic performance compared to pristine WO₃. Specifically, 5 % Cu-doped WO₃ nanoparticles exhibited consistent photocatalytic activity, with rate constants of 0.0598 min^–1 for RG and 0.0437 min^–1 for MB degradation, underscoring their potential for efficient organic pollutant removal. The stability and reusability of the catalyst were validated through reusability and scavenger experiments, confirming the robustness of the photocatalytic process. Furthermore, the toxicological effects of the photocatalytically degraded byproducts, D-RG and D-MB, were evaluated using Caenorhabditis elegans as an in vivo model, providing insights into the environmental safety of the degradation process. These findings highlight the potential of Cu-doped WO₃ nanoparticles as a sustainable and efficient photocatalyst for environmental remediation, particularly in the treatment of textile effluents.