Energy storage properties of Bi2O3-doped lead-free Ba0.85Ca0.15Zr0.1Ti0.9O3 ceramic and its switching and scaling behavior

Abstract

In this work, the intriguing crystal-structured Bi2O3 additive was doped into the lead-free Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) ceramic with different molar percentages (0.1 mol% to 1.0 mol %) to investigate its energy storage capability. The XRD data analysis confirmed the formation of a pure Perovskite phase without any presence of secondary phases in all samples. The presence of co-existing multi-phases in all prepared ceramics structures were verified by the Rietveld refinement of XRD and Raman Spectroscopy data analysis. The maximum value of the Orthorhombic (O) ⁄Tetragonal (T) phase ratio was obtained for the 0.4 mol% Bi2O3-doped sample. FESEM micrographs revealed that the smallest average grain size and the highest percentage of porosity were found for the 0.4 mol% incorporation of Bi2O3. The temperature-dependent dielectric study demonstrated that the BCZT-04Bi sample exhibited the strongest dielectric diffuse phase transition behaviour. The modelling of P-E loop analyzed the different intrinsic properties such as ferroelectricity, and switching behavior. From P-E loop measurement it was observed that among all samples, the 0.4 mol% Bi2O3-doped sample exhibited the highest room temperature energy storage efficiency of ∼67.4 % which is 18 % more than that of the pure sample. The sample also exhibited highest recovered energy density value of 117.11 mJ/cm3 at 35 kV/cm applied electric field. The scaling behavior demonstrates that the BCZT-04Bi sample exhibits outstanding frequency stability as a relaxor-ferroelectric material, with a highly sustainable recovered energy storage density. These properties make it a promising candidate for advanced electronic applications, including sensors, actuators, and frequency-pulsed capacitors. © 2025 Elsevier Ltd and Techna Group S.r.l.