Influence of manganese substitution into the A-site of perovskite type Ca<inf>1-x</inf>Mn<inf>x</inf>TiO<inf>3</inf>ceramic

Abstract

Ca 1-x Mn x TiO 3 (x = 0-1.0) perovskite ceramics were prepared by conventional solid state reaction. XRD was used to confirm the microcrystalline nature of the Ca 1-x Mn x TiO 3 crystals. For the x = 0 composition, the XRD patterns were those of a single orthorhombic perovskite while for x = 0.2-0.8, the XRD spectra were those of two orthorhombic perovskite phases: CaTiO 3 and MnTiO 3 . For x = 1, XRD pattern was that of the MnTiO 3 phase only. The morphology and particle size of the grains of the different composition were observed using SEM. The size of the particles increased from 0.2 μm to 2-3 μm as x increased from 0 to 0.6. The room temperature dielectric constant at the frequency of 110 kHz for the x = 0.2 and x = 1.0 ceramics were ∼3.41 × 10 4 and ∼4.99 × 10 3 , respectively. The ESR linewidth of samples increased with increasing manganese content due to the formation of magnetic cluster. Our ESR studies indicate that the manganese ions are in the Mn 4+ state. © 2011 Published by Elsevier Ltd and Techna Group S.r.l.