Investigation into the Synthesis, Structure and Dielectric Property of Lead-Free Double Perovskite Structured Materials

Abstract

Lead based materials have shown to be important materials showing high piezoelectricity, colossal dielectric constant, ferroelectricity along with their good mechanical behaviour and resistance to corrosion. As a result, they have wide range of applications such as sensors, actuators, detectors, batteries, lead-painting pigments etc. However, due to high toxicity of lead and its nature to accumulate in the environment with gradually increasing concentrations, increasingly more health hazards are encountered. In this regard, replacing these lead based materials by lead free material with similar/higher level of dielectric properties is the driving force for research on lead free dielectric materials. In this work, we have studied few double perovskites structured dielectric materials and their solid solutions. The present work attempts to understand synthesis, structure and dielectric property of lead free double perovskite structure BaFe0.5Nb0.5O3, BaFe0.5Ta0.5O3 and solid solution of (x) BaFe0.5Nb0.5O3–(1-x)KNbO3 (x= 0, 0.2, 0.4, 0.6, 0.8 and 1). This thesis work organized in seven chapters as given below. First two chapters describe the motivation behind the work and experimental technique used for synthesis and characterizes materials, chapter 3, 4, 5 and 6 described investigated material and chapter 7 summarizes the thesis. Details of chapters as follows,