Effect of temperature on the photocatalytic properties of TiO2-CeO2 multilayer thin films obtained by spin coating method

Abstract

TiO2-CeO2 multilayer thin films were deposited by the spin coating method and calcined at 500 and 700 °C. Thin films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and diffuse reflectance spectroscopy. Photocatalytic properties were estimated by varying the concentration of the methylene blue dye (MB) when illuminated by UV radiation. The XRD patterns showed that the temperatures of 500 and 700 °C were effective to obtain TiO2 and CeO2 phases. The difference in the homogeneity of TiO2 and CeO2 films was evident in the AFM images, where the films showed an average roughness of 2.0 and 5.3 nm, respectively. The CeO2-TiO2 thin film obtained at 700 °C showed the best photocatalytic activity, reducing the concentration of MB by approximately 80%, while the CeO2 and TiO2 films obtained at 700 °C reduced only 20% and 29%, respectively. The reuse test showed that the thin films maintained their photocatalytic activity after 4 cycles, and there was no need for thermal treatment, indicating that it is an immobilized photocatalyst with high efficiency in the degradation of organic dyes.

Heterogeneous Fenton-like catalytic degradation of phenazine dye over CeO2 (CP-2) nanoscale powder

“…Wastewaters from the textile, dyeing, leather, pharmaceutical, paper, cosmetic, plastic, and synthetic detergent industries are mainly refractory, non-biodegradable, environmentally toxic and harmful to the human health, and have potential bioaccumulation and persistence in sediments of their degradation/biotransformation by-products [1,2]. Thus, wastewater treatment, refinement, and recycling are crucial for environmental pollution control and industrial applications [2,3].…”