PHASE TRANSFORMATION, OPTICAL PROPERTIES OF TITANIA NANOMATERIALS. INVESTIGATION OF POLYMORPHIC TRANSFORMATION, BAND STRUCTURE AND PHOTORESPONSE OF TITANIA NANOMATERIALS

      Аннотация: The crystalline phase, phase transformation, optical properties, photoluminescence and photoconductivity of pure and doped Titania (TiO2) nanomaterials have been presented here. The main focus is to investigate phase transformation, phase existence on doping, photoluminescence and photoconductivity of TiO2 nanoparticles. The three polymorphs (anatase, rutile and brookite) associated with titanium dioxide (TiO2), anatase TiO2 is widely regarded as the most effective photocatalyst. In this book TiO2 nanoparticles were synthesized by sol–gel and co-precipitate methods. These TiO2 nanoparticles show anatase and anatase-rutile mixed phase at four different calcination temperatures. The structural and optical properties of prepared samples after calcination were studied. The XRD results show that anatase phase forms at 400°C and anatase – rutile mixed phase was formed at 600°C. The rutile phase percentage increases when temperature is raised to 700°C. The tensile strain has been observed at different calcination temperatures and it becomes compressive strain at 700°C, indicating that anatase phase has converted into rutile phase.

Ключевые слова: Phase transformation, Optical properties, Photoluminescence