Study of the structural phase transformation, and optical behavior of the as synthesized ZnO–SnO2–TiO2 nanocomposite

Abstract

Bulk nanocomposites ZnO–SnO2–TiO2 were synthesized by solid-state reaction method. The X-ray diffraction patterns and Raman spectra of bulk nanocomposite as a function of sintering temperature (700 °C–1300 °C) indicate that the structural phases of SnO2 and TiO2 depend on the sintering temperature while the ZnO retains its hexagonal wurtzite phase at all sintering temperatures and SnO2 started to transform into SnO at 900 °C and completely converted into SnO at 1100 °C, whereas the titanium dioxide (TiO2) exhibits its most stable phase such as rutile at low sintering temperature (≤900°C) and it transforms partially into brookite phase at high sintering temperature (≥ 900 °C). The optical band gap of nanocomposite ZnO–SnO2–TiO2 sintered at 700 °C, 900 °C, 1100 °C and 1300 °C for 16 hours is calculated using the transformed diffuse reflectance ultra violet visible near infra red (UV–VisNIR) spectra and has been found to be 3.28, 3.29, 3.31 and 3.32 eV, respectively.