Photocatalytic performance and solar cell applications of coupled semiconductor CuO– ZnO sprayed thin films: Coupling effect between oxides

Abstract

In the current study, CuO–ZnO coupled oxide thin films were deposited on glass substrates for the first time by spray pyrolysis technique. The consequences of different synthesis conditions such as molar ratio on structural, morphological, optical, and electrical properties were also studied. These physical studies were carried out by X- Ray Diffraction, scanning electron microscopy, Energy dispersive X-ray analyses (EDX), profilometer analyses, UV-VIS-NIR spectrophotometer, photoluminescence spectra, Hall Effect measurements and impedance spectroscopy. Molar ratio affects the thin films properties mainly the optical and electrical ones. The mechanisms of pure CuO and ZnO oxides and ZnO + CuO coupled oxide thin films for the degradation of methylene blue was discussed. Coupled oxide thin films show higher photocatalytic activity compared to pure oxides and the photodegradation efficiency of copper-zinc coupled oxide was found to be equal to 99% under sun light illumination. Moreover, our thin films show higher stability, recoverability and reusability under cyclic test for 9 h which makes it suitable for industrial applications. as a second applications The performance of FTO/ZnO/CuO–ZnO hetero-junction structure was investigated. This work also represents a comparative study between our synthesized thin films and other binary and coupled oxides thin films catalysis (20 catalysis) for the degradation of metylene blue and the performance of our solar cell with other structures based in ZnO + CuO coupled oxide thin films structures.