Conduction mechanism in excess Bismuth doped Strontium Bismuth Niobate ceramics

Abstract

Strontium Bismuth Niobate ceramics with excess Bismuth doping (0%wt – 20%wt) were prepared using solid state reaction method. X-ray diffraction studies reveal the decrease in c-axis orientation as bismuth content increases up to 5 ​wt%, beyond that it increases. The dielectric studies were carried out at room temperature as well as at higher temperatures. The ferroelectric properties were found to improve with excess bismuth doping to some extent (5%), indicating compensation for bismuth losses during heat treatment. Temperature dependent dc conductivity studies were done and attempts were made to explain extrinsic and intrinsic conduction mechanisms in Strontium Bismuth Niobate. In low temperature region, the activation energy was found to be very low (0.08eV–0.16eV), which increases (1.07eV–1.14eV) due to introduction of intrinsic defects. A detailed conduction mechanism is presented with excess bismuth doping in Strontium Bismuth Niobate.