Synthesis,consolidation and dielectric properties of BLT ceramics processed by M-PVA gel ignition technique

Abstract

Abstract

Polycrystalline samples of lanthanum modified bismuth titanate ceramics with composition Bi_3·25La_0·75Ti₃O₁₂ (BLT) were prepared at three different sintering temperatures (1050, 1100 and 1150°C) using M-PVA gel ignition technique. The samples were characterised for structural and electrical properties. A significant amount of as burnt BLT powder was found to be crystalline in nature having a yellowish colour. Very fine BLT nanoparticles were characterised by TEM analysis. Single phase with orthorhombic crystal structure was observed for all the samples, confirmed by X-ray analysis. Dielectric properties were studied as a function of frequency and temperature. More than 95% relative density was observed for all the three sintered samples. The sample sintered at 1100°C showed highest dielectric constant and relative density and lowest loss.