Dielectric energy storage materials for space sensors: effect of processing on the performance

Abstract

This paper explores the development of innovative materials for the dielectric energy storage for space components. The CaCu3Ti4O12 or CCTO belonging to perovskite family is of interest due to its colossal dielectric constant. It was demonstrated that materials synthesized at low temperature show nonequilibrium state and exhibit differences in the dielectric and resistivity values. The goal is to obtain high dielectric constant along with high resistivity values for achieving enhanced breakdown voltage. By using other members of the perovskite structures, it was demonstrated that similar colossal dielectric constant is observed and is dependent on processing methods. We have used heterovalent and dissimilar sized atom to replace Ca+2 ion. Accordingly, we replaced Ca+2 ion with heavy Ga+3 ion and developed gallium-based material system, Ga2/3 Cu3Ti4O12. Following successful synthesis, we measured its dielectric constant and resistivity and compared with CCTO material system. Results of five sets of samples showed that lower temperature processing demonstrated mechanism of grain growth, but due to copper flow in high temperature processed samples dielectric constant and resistivity values were different.