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

Abstract

MnTiO3is a semiconductor that has relevant dielectric and optical properties. For the synthesis of manganese titanate (MnTiO3) 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 MnTiO3bonds. 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 MnTiO3of 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.