Impact of phase transition sequence on the electrocaloric effect in Pb(Nb,Zr,Sn,Ti)O-3 ceramics
The phase transition sequence in PbZrO3-based ceramics can be readily altered by chemical modification. In Pb0.99Nb0.02[(Zr0.57Sn0.43)(0.92)Ti-0.08](0.98)O-3 (PNZST 43/8/2), the sequence is ferroelectric-antiferroelectric-paraelectric during heating, while in Pb0.99Nb0.02 (Zr0.85Sn0.13Ti0.02)(0.98)O-3 (PNZST 13/2/2), it is antiferroelectric-ferroelectric-paraelectric during heating. The electrocaloric effect associated with the antiferroelectricferroelectric phase transition is studied in both ceramics via indirect measurement. PNZST 43/8/2 is observed to display a positive electrocaloric effect; in contrast, PNZST 13/2/2 exhibits a negative effect.