Enhanced energy-storage performance of Pb0.925La0.05Zr0.95Ti0.05@xwt%SiO2 composite ceramics.

• The PLZT@SiO 2 composite ceramic was prepared by the Stöber method, which increased the density of the ceramic, and greatly improved the energy storage density. • SEM results indicate that SiO2 weakens the crystallinity of the ceramics and restricts the grain growth of all the specimens. • Compared with the single-phase PLZT ceramics, although the electric breakdown field strength of the core-shell structure sample has not improved much, its energy storage density has increased significantly. Pb 0.925 La 0.05 Zr 0.95 Ti 0.05 @ x wt%SiO 2 (PLZT@ x wt%SiO 2 , 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 Stöber 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 SiO 2 weakens the crystallinity of the ceramics and restricts the grain growth of all the specimens. When the concentration of SiO 2 is 3 wt%, the sample shows better energy storage characteristics, the value of W re of this sample can reach 2.29 J/cm3; In addition, temperature (T) will induce a phase change in the sample. When T < 50 ℃, sample S3 is ferroelectric phase, when T is in the range of 50–130 ℃, 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 η are 317.39 % and 25.04%, respectively. The core-shell structure samples prepared by the Stöber method can increase the energy storage density by reducing the turnover electric field. The energy storage density has increased from 0.3 J/cm3 to 2.29 J/cm3. [ABSTRACT FROM AUTHOR]