Calcination Temperature Dependent Dielectric Properties of Nanocrystalline BaSnO₃

Abstract

BaSnO 3 nanocrystals were synthesized using a simple solid-state route varying the calcination temperature to investigate the effect of grain growth on dielectric properties of this popular perovskite oxide. Duration of calcination was optimized to obtain the pure phase. The samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray analysis to investigate crystal structure, morphological information, and elemental composition respectively. The average crystallite size increased from 35 to 49 nm, whereas the porosity decreased from 20.41% to 11.03% with tuning of calcination temperature. The dielectric constant and conductivity increased with calcination temperature whereas the tangent loss maximum was decreased by ∼9%. A non-Debye type relaxation mechanism was confirmed for all samples using Cole-Davidson relations. The outcomes of the electrical properties were correlated with the grain-grain boundary effect, porosity, and brick layer model. It was clearly observed that the effect of high calcination temperature can enhance the room-temperature dielectric constant and conductivity of the nano-BaSnO 3 perovskites.