Enhanced photocatalytic activity of Er-Ce co-doped ZnO nano-cauliflower structured films deposited by spray pyrolysis

Organic dyes are toxic and carcinogenic and their release into the environment causes water pollution and poses significant health risks to all living beings. Effective and environmentally friendly approaches such as photocatalysts are essential to deal with organic dyes in industrial wastes. The affordable and environmentally friendly properties of ZnO make it a superior photocatalyst compared to other materials. The main objective of the study is to evaluate the degradation efficiency of Er-Ce co-doped ZnO films as photocatalysts under methylene blue dye, which has not been studied in the literature before. This study presents a review of the structural, optical, surface and photocatalytic properties of Er-Ce co-doped ZnO nano-cauliflower like films synthesized by spray pyrolysis technique. The increase in the optical band gap values with the increase of Er-Ce doping ratio is due to the Burstein-Moss effect, which causes a blue shift in the band gap. Morphological changes on the film surfaces were revealed by FESEM and it was observed that as the Er-Ce content increased, the surface morphology showed a nano-cauliflower like structure. The photocatalytic activity of ZnO:Er:Ce thin films was evaluated using the organic dye methylene blue (MB) under UV irradiation, and it was revealed that MB dye could degrade 98.5 %. This study predicts that Er-Ce co-doped ZnO catalysts may be a promising candidate for the degradation of organic dyes in environmental remediation applications and contributes to the further development of environmentally friendly photocatalytic materials. Furthermore, the mechanism that performs photocatalysis has been investigated by scavenger experiments, and it was observed that .OH.