Enhanced Ferroelectric and Dielectric Properties in Bi0.5Na0.5TiO3 Doped with BaTiO3 (BNT-BT) Nanoparticles for High Energy Storage Device

Abstract

Nanoparticles of lead-free Bi0.5Na0.5TiO3 doped with BaTiO3 (BNT-BT) have been fabricated by the auto-combustion sol-gel method. A structural and morphological analysis of the developed material has been performed by using XRD and FESEM. Also, a temperature and frequency (100Hz-1MHz) dependent dielectric study of BNT-BT nanoparticles has been conducted, resulting in a variation that occurs at 120.83 °C due to transition from ferroelectric to antiferroelectric phase, followed by a sudden increase due to paraelectric phase formation. Additionally, as frequency increased, the dielectric constant decreased exhibiting Maxwell-Wagner polarization. The ferroelectric study has been done by using PE loop at room temperature (28 °C). The maximum value obtained for remanent polarization and saturation polarization is 1.73 μC/cm2 and 3.75 μC/cm2 respectively at an applied electric field of 28 kV/cm. The value for the recoverable energy storage density (W1) is 0.0483 J/cm3, energy loss density(W2) is 0.05378 J/cm3 and its efficiency (Ƞ) is 47% at an applied field 28 kV/cm. The obtained results for the BNT-BT nanoparticles are remarkable for energy storage devices, and they further indicate their potential for energy harvesting and high piezoelectric sensors for industrial purposes.