Enhanced Energy-Storage Performance of Pb0.925La0.05Zr0.95Ti0.05@xwt%SiO2 Composite Ceramics

Pb0.925La0.05Zr0.95Ti0.05@xwt%SiO2 (PLZT@xwt%SiO2, x = 0, 1, 2, 3 and 4, marked as S0, S1, S2, S3, S4 respectively) ceramics were prepared by combining conventional sol-gel method with Stober method, the microstructure, electrical properties and energy storage characteristics were comparatively investigated. TEM analysis prove that samples S1, S2 and S3 present core-shell structures. SEM results indicate that SiO2 weakens the crystallinity of the ceramics and restricts the grain growth of all the specimens. When the concentration of SiO2 is 3 wt%, the sample shows better energy storage characteristics, the value of W-re of this sample can reach 2.29 J/cm(3); In addition, temperature (T) will induce a phase change in the sample. When T < 50 degrees C, sample S3 is ferroelectric phase, when T is in the range of 50-130 degrees C, sample S3 is coexistence of anti-ferroelectric and ferroelectric phase, showing double electric hysteresis loops. In this temperature range, the temperature stability of sample S3 is the poorest, and the increases in W-re density and eta are 317.39% and 25.04%, respectively. The core-shell structure samples prepared by the Stober method can increase the energy storage density by reducing the turnover electric field. The energy storage density has increased from 0.3 J/cm(3) to 2.29 J/cm(3). (C) 2021 Elsevier B.V. All rights reserved.