The effect of Al element on structural, optical, electrical, surface and photocatalytic properties of Sol-gel derived ZnO films

ZnO films are remarkable materials as transparent front contact in photovoltaic solar cells and as photocatalyst in eliminating problems such as water, air and environmental pollution caused by industrial wastes. In this study, it was tried to improve the properties of pure-ZnO films for photovoltaic and photocatalytic applications by incorporating Al element. ZnO and ZnO:Al films were economically produced by the solgel spin coating technique. The crystallization levels were investigated by XRD, and optical band gap values were determined using optical method. Defect states were investigated by photoluminescence spectra. Surface morphologies were analyzed by AFM-FESEM, and elemental analyses were performed by EDX. Photocatalytic tests were carried out using methylene blue. The Al doping process resulted in an increase in the degradation efficiency of the methylene blue, and the best photocatalytic effect was obtained with AZO-4 films with higher degradation value (94%). Besides, the electrical resistivity of pure-ZnO films was reduced from 3.57 x 10(2) omega cm to 5.08 x 10(-3) omega cm with Al additive ratio of 4%. We think that lower surface roughness of AZO-4 film having high electrical conductivity and figure of merit may reduce the short-circuit effect in solar cell applications.

Automated summary

This study aimed to improve the properties of pure-ZnO films for photovoltaic and photocatalytic applications by incorporating Al element. ZnO and ZnO:Al films were economically produced by the solgel spin coating technique. The results showed that Al doping process led to an increase in the photocatalytic degradation efficiency and conductivity of the films.