| Popis: |
Ilmenite (FeTiO3) is an attractive semiconducting compound with a wide bandgap that enables its application in spintronics, photocatalysts, optoelectronics, chemical catalysts and high temperature integrated circuits etc. In particular, on going to nano sizes, variations in the physical properties are observed and are often enhanced. In this study, variation in the structural, thermal and optical properties of FeTiO3 ilmenite compound on going from bulk to nano sizes are analysed. Nano samples have been prepared by milling in a SPEX8000M high energy ball mill for 15 and 60 minutes using tungsten carbide (WC) vial and balls. Variation in the particle size and strain through ball milling has been analysed using X-Ray Diffraction technique which confirms the formation of hexagonal structure of FeTiO3 without any additional phases for bulk and nano sized samples (∼35 and 15 nm) respectively. The thermal behaviour of the compound is studied and an exothermic peak is found in the 15 minutes ball milled sample at 642K indicative of a phase change. Band gap has been calculated from the absorption spectrum recorded on a UV-visible spectrophotometer and shows a decrease in bandgap with an increase in the milling time. The calculated values of the band gap are 3.50, 3.44 and 3.43 eV respectively for unmilled, 15 and 60 minutes milled samples. |
