Effect Of Milling Frequency On The Structural And Dielectric Properties Of Tetragonal Srtio3 Nanoceramics

Abstract

In this research work, we qualitatively study the structural and dielectric properties of tetragonal SrTiO₃ nanoceramics. The ferroelectric material with perovskite structure has various applications in different fields such as electronics and energy storage devices. Strontium titanate (SrTiO₃) among all ferroelectric materials has attractive attention due to its numerous applications as tunable microwave capacitor, thermistors, varistors sensors and microwave filters. Strontium titanate (SrTiO₃) nano-ceramics powders are prepared by solid state reaction route. Nano powders of strontium titanate are prepared by high energy planetary milling technique. The samples are prepared at various milling frequency of 15Hz- 50Hz for 4 h of milling time and then calcined at 1200 C for 60hrs. The calcined powders are characterized by XRD and Impedance analyzer. XRD studies reveal the p-cubic structure when the samples are milled at 15Hz to 35Hz of milling frequency and belong to space group of Pm3m. The phase transition from p-cubic to p-tetragonal was observed for the sample milled at 40Hz of milling frequency. After 40Hz of milling frequency no phase transitions in crystal structure of strontium titanate was observed. Only strengthening and phase stability of perovskite tetragonal SrTiO₃ was observed with increasing milling frequency. Dielectric and impedance analysis have been examined by impedance analyzer with a frequency range of 20Hz to 20MHz.Room temperature dielectric properties show immense dielectric constant value of ~ 73183.3 at 50Hz of milling frequency. The tangent loss is minimum for this sample. Colossal dielectric constant in nano-ceramics SrTiO₃ has impending applications such as in microelectronic devices as well as for the advancement of innovative capacitive data storage devices.