High energy storage density and efficiency in AgNbO3 based relaxor antiferroelectrics with reduced silver content

Abstract

Silver niobate based lead-free antiferroelectric ceramics have demonstrated great advantages, but the high consumption of noble metal silver may restrict their commercial application. In this work, Na+ and Ta5+ co-modified (Ag1-xNax)(Nb1-yTay)O3 (100xNa-100yTa) ceramics were investigated, aiming to reduce the silver consumption and achieve good energy storage properties. The Na+ tended to increase M2-M3 phase transition temperature (TM2-M3), while Ta5+ was more likely to reduce TM2-M3. A new current peak (ER) was observed for the first time in all current-electric field curves. As expected, a room temperature M2-M3 phase boundary with relaxor AFE property was realized in 40Na-65Ta with obviously reduced silver content, in which high recoverable energy storage density (Wrec) of 6.5 J/cm3 and good energy storage efficiency (η) of 78% were achieved. This work demonstrates a strategy to realize relaxor antiferroelectrics in AgNbO3 based ceramics for energy storage performance, and promotes the commercialization potential.