Sunlight activated S-scheme ZnO-CoTe binary photocatalyst for effective degradation of dye pollutants from wastewater

In the present work, ZnO-CoTe photocatalyst with S-scheme transfer mechanism was successfully synthesized by hydrothermal method and characterized via various analytical techniques. The grown ZnO-CoTe nanocomposite was tested for the photodegradation of cationic and anionic dyes under sunlight irradiation. Compared with pure ZnO and CoTe catalysts, ZnO-CoTe nanocomposite exhibited superior photocatalytic degradation and degraded 98.5% methyl red (MR) and 99.8% methylene blue (MB) dyes within 60 min of sunlight illumination, having a higher rate constant 0.0626 min⁻¹, and 0.0929 min⁻¹, respectively. Furthermore, the band structure of ZnO and CoTe align such that the S-scheme charge transfer mechanism occurred, which could effectively improve charge carriers migration and separation, leading to high photocatalytic degradation capability than that of pure ZnO and CoTe catalysts. Because of its promising photocatalytic performance, the ZnO-CoTe nanocomposites can be effectively used for future environmental applications.