Effect of Annealing Temperature on Structural and Optical Properties of ZnTiO3 Perovskite Layers Deposited on Silicon for Photocatalytic Applications

摘要

In this paper, we investigate the effect of annealing temper- ature on structural, optical, and photocatalytic properties of nanostructured ZnTiO3 thin films deposited on Si substrates. ZnTiO3 coatings were prepared by consecutive sol-gel method and further deposited on Si substrates by spin-coating. The obtained films were annealed at three various temperatures namely 700°C, 800°C, and 900°C. X-ray diffraction analysis shows that the crystallite size of the films grows from 100 to 125 nm as the annealing temperature increases from 700 to 900°C. At the same time, the roughness increases from 232 to 289 nm and the band gap dwindles from 3.73 to 3.05 eV. ZnTiO3 coatings annealed at 700°C exhibits the highest photo- degradation rate about 74% to catalyze the degradation of the Methylene Blue aqueous solution. We demonstrate that this high photocatalytic activity is attributed to the structural and optical properties of prepared samples.