Optical and electrical properties of Ti1-XSnXO2 nanoparticles

Abstract

In this work we successfully doped Sn to TiO2 in an anatase and rutile structural form from 0.2% to 1% by standard peptization method. Crystallographic properties and reduction in size is confirmed by XRD, Scherrer formula confirms the average crystallite size from 92 to 40 nm. UV–Visible spectra confirms the increment in band gap and absorption is in visible region from 420 to 435 nm. SEM images show the reduction in the size and tending towards spherical in nature with average particle size from 110 to 40 nm. EDAX confirms the doping is successful as with the desired amount from 0.2% to 1%. Pellet form of these samples were studied in the frequency range from 1 MHz–10 MHz, which shows the ε′ predominant in the lower frequency region, which is more for the particle size of 67 nm at 1 MHz, then it decreases instantly with increase in frequency then saturates with increase in frequency due to charge carriers, with hopping conduction is prominent at this region. ε′′ and tanδ show the same nature loss is minimum in lower frequency and slightly increases with the frequency and then decreases at higher frequencies, and it decreases with decrease in particle size due to size effect. σac Increases with increase in frequency, at 1 MHz σac maximum for average particle size and it decreases with decrease in particle size due to hopping conduction become predominant.