EFFECT OF CALCINATION TEMPERATURE ON THE BAND GAP ENERGY OF TiO2/ZnO SYNTHESIZED BY SOL-GEL METHOD Siti Oryza Sativa1,*, Muhammad Ali Zulfikar1, Yanti Rachmayanti1, and Wibawa Hendra Saputera2
1Department of Chemistry, Institut Teknologi Bandung, Jawa Barat, 40132, Indonesia
2Department of Chemical Engineering, Institut Teknologi Bandung, Jawa Barat, 40132, Indonesia
Abstract
Metal oxide nanoparticles can be synthesized by sol gel method which a wet chemical method for fabrication of nanostructural materials. Binary oxide system semiconductors of TiO2 ZnO have been synthesized by simple sol gel method followed by calcination temperature at 500 C, 600 C, and 700 C. The band gap energy was measured using spectrophotometer Ultra Violet Visible and Diffuse Reflectance. We calculate both of direct and indirect transition electronic using Kubelka Munk function and Tauc plot. The result showed that increasing calcination temperature, lowering band gap energy of synthesized materials. Lowest band gap was observed on TiO2 ZnO calcinated at 700 C which 2.98 eV for direct transition electronic and 2.85 eV for indirect transition electronic. For further study, it indicates that synthesized materials could be used as photocatalysis material under visible light spectrum ranges from 410 to 440 nm. In conclusion, calcination temperature can decrease the band gap energy of TiO2 ZnO.
Keywords: TiO2/ZnO- sol gel- photocatalyst- calcination- band gap.
