Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Türkiye
Tezin Onay Tarihi: 2014
Tezin Dili: İngilizce
Öğrenci: Lütfi Ağartan
Danışman: ABDULLAH ÖZTÜRK
Özet:Effects of water/Ti precursor molar ratio (R ratio) and calcination regime on the photocatalytic properties of undoped, boron (B) doped, zirconium (Zr) doped, and B and Zr co-doped TiO2 powders synthesized by sol-gel process were researched. Undoped powders were synthesized for R ratio of 1, 3, 5, 10, 30, and 50 while doped and co-doped powders were synthesized for R ratio of 50. Undoped powders were calcined at 300, 400, and 500oC for 1, 2, and 3 h while doped and co-doped powders were calcined at 300 and 500oC for 1 h. X-ray diffraction analysis indicated that doped and undoped powders composed of only anatase crystals, except the undoped powders synthesized for low R ratio calcined at 500oC. Rietveld analyses suggested that B and Zr were successfully doped into the crystal structure of TiO2 and changed the lattice parameters. Scanning electron microscopy investigations revealed that all powders were in the range of 15 to 40 nm in size and were highly agglomerated. Diffuse reflectance spectroscopy measurements showed that all powders had band gap energy of around 3.2 eV and their reflectance could be shifted to visible light region of the electromagnetic spectrum. Upon B and Zr co-doping better methylene blue degradation was achieved in UV light and daylight. The improvement in photocatalytic performance due to co-doping was attributed to the changes in structural and morphological features.