Microwave Synthesis of Nanoparticulate SmFeO₃ and Its Characterization

Single phase perovskite SmFeO₃ nanoparticles were synthesized using a simple microwave method using Fe(NO₃)₃· 9H₂O and Sm(NO³)³ · 6H₂O. The resulting samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area measurement, UV-visible diffuse reflectance spectroscopy (DRS) and Fourier transform infrared spectroscopy (FTIR). XRD and SEM results demonstrate the successful synthesis of nanocrystalline SmFeO₃ and show an average grain size of 50-60 nm. The single phase structure and optical properties of SmFeO₃ were maintained after calcination at 1000 °C. The prepared nanocrystalline SmFeO₃ displays excellent thermal stability and strong visible-light absorption, with an absorption onset of 540 nm or so. The photocatalytic experiment involving the decomposition of methyl orange under visible-light irradiation shows the high photocatalytic activity of the nanoparticles.