Synthesis, characterisation and optical properties of MnTiO₃nanopowders

Pure manganese titanate (MnTiO3) nanopowders have been synthesised by stearic acid gel method. Structural investigations by X-ray diffraction and scanning electron microscopy confirm that the synthesised material is MnTiO3 with rhombohedral crystal structure. Transmission electron microscopy showed that the particle sizes are in the range of 22–30 nm. The formation of MnTiO3 is further supported by the FT-IR and energy dispersive X-ray spectra. An optical band gap of 3.18 eV is determined for MnTiO3 nanopowders from the UV–vis absorption spectrum. A broad emission band with maximum intensity at around 487 nm is observed in the photoluminescence spectra of MnTiO3 nanopowders at room temperature depicting the blue emission, which can be attributed to the 4T2 (4G) → 6A1 transition in the material.