The functionalization of morphological, structural and optical properties of Fe doped SnO₂ nanocrystals synthesized by the sol–gel method

In this study, undoped SnO₂ nanocrystals and SnO₂ nanocrystals with Fe dopant at different atomic ratios (0, 5, 10, 15 and 20%) were synthesized by using the sol–gel method. SnO₂ based nanoceramic materials, which can be used in several scientific researches and high technology applications, are easily synthesized, and have superior properties, were produced by using this method. The changes in the structural, morphological and optical properties of the Fe-doped samples were investigated through the X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier Transform IR (FT-IR), and UV–Vis–NIR spectroscopy. XRD spectra obtained from the samples showed that the samples had a tetragonal crystal structure and the cassiterite phase. The crystal size of the samples decreased from 30.28 to 24.84 nm along with the rate of the Fe dopant. SEM images revealed that the grain size of SnO₂ distinctly decreased since it prevented the grain growth of Fe. In compliance with the results of XRD and EDX, FTIR spectra displayed the peaks confirming that the doped Fe was added in the structure of SnO₂. The optical band gaps of the samples were calculated from the diffuse reflectance curves using the Kubelka–Munk function. It was observed that Eg values of the samples increased from 3.58 to 3.61 eV depending on Fe dopant.