Ce-doped TiO₂-zeolite fibers: visible light-driven photocatalysts for indigo dye degradation

Indigo dye is a poisonous dye that threatens human health by polluting the environment. Therefore, we prepared a visible light-sensitive photocatalyst to eliminate indigo dye especially from water sources. In this study, sol-gel and electrospinning methods have been performed to synthesize Ce-doped TiO₂-zeolite fibers for indigo degradation. The structural and optical properties of the synthesized fibers were investigated by XRD, SEM, EDX, and UV-Vis spectrophotometer techniques. It has been shown that 3% Ce-doped TiO₂/zeolite fibers have the highest photocatalytic activity with 100% degradation after 150 h, showing that the light absorption of TiO₂ expands into the visible light area by Ce doping and absorption into the zeolite. The recyclability analyses of the spent photocatalyst exhibited 87.0% degradation of indigo after four cycles, demonstrating the stability of the fiber. An effective photocatalyst has been obtained by improving the photocatalytic and electrochemical properties thanks to the fibers' high surface area and the zeolite's porous structure. Based on these findings, the study reveals the significant potential of Ce-doped TiO₂/zeolite fibers for the purification of wastewater under visible light.