Y doping and grain size co-effects on the electrical energy storage performance of (Pb0.87Ba0.1La0.02) (Zr0.65Sn0.3Ti0.05)O3 anti-ferroelectric ceramics

(Pb0.87Ba0.1La0.02) (Zr0.65Sn0.3Ti0.05)O3+x mol% Y (PBLZST-x, x=0–1.25) anti-ferroelectric (AFE) ceramics have been prepared by the solid-state reaction process, and the effect of Y-doping on the microstructure and electrical properties has been investigated. When the Y content increases from 0 mol% to 1.25 mol%, the average grain size of the PBLZST ceramics decreases by more than 3 times (from 4.7 μm to 1.5 μm). The doping and grain size co-effects lead to a significant increase in the AFE-to-FE and FE-to-AFE phase transition electric field (EF and EA), and result in a decrease in the width of the double hysteresis loops. As the Y content increases from 0 mol% to 0.75 mol%, the EF increases from 53 KV/cm to 83 KV/cm and the EA increases from 35 KV/cm to 72 KV/cm. The large recoverable energy density of 2.75 J/cm3 and the high energy efficiency of 71.5% can be achieved when 0.75 mol% Y is doped. The results indicate that Y-doping is an effective method to modulate the average grain size and improve the energy storage performance of the PBLZST anti-ferroelectric ceramics.