Study of structural, optical, and morphological characteristics of manganese titanate (MnTiO3) obtained by combustion reaction using microwave energy

Abstract

MnTiO 3 is a semiconductor that has relevant dielectric and optical properties. For the synthesis of manganese titanate (MnTiO 3) powders, the combustion method via microwave and subsequent calcination at 500, 700, and 900 °C were used. The structural, morphological, and optical properties of the samples were investigated. X-ray diffraction analyzes were performed, where it was possible to index all peaks in the pyrophanite phase with a rhombohedral structure for the 900 °C sample. FTIR spectra corroborate the diffraction results, showing the presence of the vibrational modes characteristic of the MnTiO 3 bonds. SEM images revealed the formation of distorted nanobands with an average diameter of 320 nm. The optical spectrum obtained from the UV-vis absorption spectroscopy suggested a bandgap for MnTiO 3 of around 3.18 eV. The present work showed that combustion synthesis via microwave is efficient for the production of pure manganese titanate after calcination at 900 °C for 2 h.