Studying Structural and Optical Properties of TiO2–SnO2 Core–Shell Synthesized by Sol–Gel Route

Abstract

AbstractHerein, the TiO2–SnO2 core–shell structures with the core‐to‐shell molar ratios of 5:0.5, 5:0.67, and 5:1 are synthesized by the sol–gel route, and then the structural and optical properties of the synthesized samples are investigated. In order to characterize the samples, the XRD, Raman, FESEM, and TEM techniques are used for their structural verification, while the UV–visible and photoluminescence spectra are used for their optical characterization. The XRD results obtained showed that the annealed TiO2 sample has an anatase tetragonal structure and that the core–shell samples contain the diffraction peaks of both the core TiO2 and the shell SnO2. The XRD results obtained are supported by Raman spectroscopy. The TEM images obtained show evidence of the formation of the composite (core–shell) nanostructure in the samples. The optical investigation shows that the band gaps of the core–shell samples are indirect, like the TiO2 core itself, and increase with an increase in the core‐to‐shell molar ratio. These results also show that the synthesized core–shell samples are suitable candidates for use in optoelectronic devices.