Superior energy-storage properties in (Pb,La)(Zr,Sn,Ti)O-3 antiferroelectric ceramics with appropriate La content

Abstract

Antiferroelectric (AFE) ceramics based on Pb(Zr,Sn,Ti)O3 (PZST) have shown great potential for applications in pulsed power capacitors because of their fast charge-discharge rates (on the order of nanoseconds). However, to date, it has been proven very difficult to simultaneously obtain large recoverable energy densities Wre and high energy efficiencies η in one type of ceramic, which limits the range of applications of these materials. Addressing this problem requires the development of ceramic materials that simultaneously offer a large ferroelectric-antiferroelectric (FE-AFE) phase-switching electric field EA, high electric breakdown strength Eb, and narrow polarization-electric field (P-E) hysteresis loops. In this work, via doping of La3+ into (Pb1-1.5xLax)(Zr0.5Sn0.43Ti0.07)O3 AFE ceramics, large EA and Eb due to respectively enhanced AFE phase stability and reduced electric conductivity, and slimmer hysteresis loops resulting from the appearance of the relaxor AFE state, are successfully obtained, and thus leading to great improvement of the Wre and η. The most superior energy storage properties are obtained in the 3 mol% La3+-doped (Pb1-1.5xLax)(Zr0.5Sn0.43Ti0.07)O3 AFE ceramic, which simultaneously exhibits at room temperature a large Wre of 4.2 J/cm3 and a high η of 78%, being respectively 2.9 and 1.56 times those of (Pb1-1.5xLax)(Zr0.5Sn0.43Ti0.07)O3 AFE ceramics with x = 0 (Wre = 1.45 J/cm3, η = 50%) and also being superior to many previously published results. Besides, both Wre and η change very little in the temperature range of 25–125 °C. The large Wre, high η, and their good temperature stability make the Pb0.955La0.03(Zr0.5Sn0.43Ti0.07)O3 AFE ceramic attractive for preparing high pulsed power capacitors useable in various conditions.