Effect of Calcination Temperature on the Structural and Optical Properties of FeSbO₄ Nanostructures

Abstract

In the present work, a Solvothermal method is employed to prepare reactive nanoparticles of FeSbO4 by varying synthesis conditions. A systematic evolution of FeSbO4 phase formation as a function of calcination temperature is monitored by in situ Powder X‐ray Diffraction (pXRD). XRD data reveals that the pure FeSbO4 phase is obtained at calcination temperature of 700 °C and above which can be indexed to rutile FeSbO4 phase. However, below this, temperature various secondary phases are observed. Surface morphology analysis shows pellet‐shaped nanoparticles with narrow size distribution and particle size below 100 nm. Moreover, material calcined at 900 °C shows large‐size particles due to fusing and agglomeration. Energy‐dispersive X‐ray spectroscopy (EDS) data reveals the purity and elemental composition of the as‐synthesized nanostructures. The spectroscopic studies by Fourier Transform Infrared spectroscopy (FTIR) give information about the presence of various functional groups in FeSbO4 nanoparticles in the range 400–900 cm−1. The UV–vis spectroscopy analysis presents absorption peak in the range of 208–228 nm for FeSbO4 nanoparticles. A band gap of around 3.85 eV is obtained from Tauc's plot. The FeSbO4 nanoparticles can be used for sensor, for electrochemical applications, and also as possible oxide thermoelectric with suitable composites.