Preparation of boron-zirconium co-doped photocatalytic titanium dioxide powder


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Metalurji ve Malzeme Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2013

Öğrenci: TOLGA TOKMAKCİ

Danışman: ABDULLAH ÖZTÜRK

Özet:

A titanium dioxide powder co-doped with boron and zirconium was prepared by mechanical ball milling. Photocatalytic performance of the powder was evaluated by degradation of methylene blue (MB) solution under UV illumination. XRD patterns were refined by Rietveld analysis method to obtain accurate lattice parameters and position of the atoms in the crystal structure of TiO2. XRD analysis indicated that the B and/or Zr doped TiO2 powders composed of anatase and did not exhibit any additional phase. Rietveld analysis suggested that dopant B and Zr elements were successfully weaved into crystal structure and distorted the lattice of TiO2. The highest distortion was obtained by co-doping. SEM investigations confirmed that mechanical ball milling technique led to a decrease in particle size of TiO2 powder. XPS analysis revealed that dopant B and Zr atoms did not appear in any form of compound including Ti and O elements. Results of photocatalytic activity test suggested that boron and zirconium co-doped TiO2 particles exhibited a better visible light response and photocatalytic activity than that of mono element doped TiO2 (i.e. B-TiO2 and Zr-TiO2) and undoped TiO2 particles. A 20% improvement in photocatalytic activity of reference TiO2 powder (powder ball milled without dopant addition) was achieved by B and Zr co-doping. The enhanced photocatalytic activity is attributed to synergistic effects of B-Zr co-doping the lattice of TiO2 as well as particle size reduction.