Application of Tungsten Trioxide-Loaded Gelatin-Polyethylene Glycol Film for Enhanced Photocatalysis: Unraveling the Role of Catalyst Reusability in Wastewater Treatment

Photocatalytic degradation is a promising approach for mitigating water pollution, with catalyst reusability being essential for achieving sustainable treatment processes. In this study, Gelatin-(Polyethylene glycol, PEG) composite films were prepared and modified by incorporating tungsten trioxide (WO₃) at different concentrations- to enhance photocatalytic performance. The photocatalytic activity and reusability of the WO₃-loaded Gelatin-PEG (WO3@Gelatin-PEG) films were systematically evaluated using Rhodamine-B (Rh-B) and methyl orange (MO) as model organic dyes under visible-light irradiation. The effects of catalyst loadings and initial dye concentration on the degradation efficiency and reaction kinetics were investigated. The results revealed that WO₃ incorporation significantly improved photocatalytic activity, and dye degradation followed pseudo-first-order kinetics under the investigated conditions. Reusability tests demonstrated that the composite films retained a substantial portion of their photocatalytic activity over multiple cycles. Overall, this study demonstrates the potential application of WO₃-loaded gelatin–PEG (WO3@Gelatin-PEG) composite films as reusable, visible-light-responsive photocatalysts and contributes to the development of sustainable photocatalytic systems for wastewater treatment.