Titanium dioxide shows polymorphism on heating to a higher temperature. This transformation is strongly dependent on temperature and time of heating. Pure Titania pulp containing amorphous titania was heated at different temperatures and for different times. Above 650 degrees C the anatase phase evolved and between 900-1000 degrees C, an anatase-rutile transformation occurred. The anatase-rutile transformation in TiO2 in the presence of CuO and MnO2 was investigated. The different phases of 1102 were determined using powder XRD. Other methods such as chemical analysis, scanning electron microscopy, surface area measurements and crystallite size calculations were used for the characterization of the samples. The transformation temperature was found to be much lowered in the presence of the above metal oxides. Also the method of preparation of metal oxide doped TiO2 affects the polymorphism.

Keywords: calcination; sensors; TiO2; transition metal oxides; X-ray methods