Research Projects

Lead free dielectric energy storage ceramics are one of the key sustainable solutions to deal with the energy crises that has been witnessed in last decades with least impact on the environment. Dielectric capacitors offer high power density, ultra-fast charging and discharging speed, moderate energy density, efficiency, structural stability in much convenient way as compared to conventional energy storage devices e.g., batteries and electrochemical cells. However, low energy storage density and efficiency of dielectric capacitor limits their utility for next generation electronics. The energy storage density of the dielectric ceramic mainly determined by dielectric constant, breakdown voltage and remanent polarization, which are interrelated and almost impossible to get desirable values in a single material. Further, various approaches viz. domain engineering, super paraelectric engineering, defect engineering, bandgap engineering, microstructural optimization etc. were adopted to improve the energy density in dielectric ceramics. However, improvement in overall performance of dielectric energy storage ceramics is still a challenge. In recent years, high-entropy alloys, metals, and ceramics have attracted material scientists due to their excellent thermal and structural stability with improved efficiency. High-entropy oxides are metal oxides with five or more types transition metals with different molar fractions (5 to 35%), which has been proved to exhibit high energy density (up to 13 J/cm³) and efficiency (~90%). This new strategy is also promising for miniaturized power electronics along with existing pulsed power electronics and hybrid electric vehicles. Two different approaches were adopted in this regard i.e., high entropy ceramics as a matrix or as additive to some component. Both the approaches have resulted in breakage of long-range order, nano domain, random field generation, delay in saturation, smaller remanent polarization leading to highly efficient energy storage performance. This project aims to systematically report the evolution of electrical storage performance with configurational entropy of ABO₃ (A = Mg, Ba, Sr, Ca, and B = Ti, Zr) ceramics with different molar ratios of metal elements via solid-state reaction method. Secondly, the sintering temperature of as prepared single-phase ceramics shall be optimized carefully to ensure best microstructure for desired electric storage capacity. Lastly, the optimized ceramic pellet shall be carried forward for capacitor fabrication. Optimization of synthesis conditions for bulk production of HEC and HEC based capacitors will be promising for ongoing and upcoming electronic industries in India.