0.92 Pb(Mg1/3Nb2/3)O3 - 0.08 PbTiO3 relaxor ferroelectrics modified with different dopants for electrocaloric cooling application

In the present work we investigate the influence of acceptor (K+, Cu+, Li+), donor (La3+, Bi3+, Eu3+, Nd3+, Y3+, Cr3+) and charge equivalent dopants (Sr2+, Co2+, Mn2+, Ta5+) on the dielectric and ferroelectric behavior of 0.92 Pb(Mg1/3Nb2/3)O3-0.08 PbTiO3(0.92PMN-0.08PT). As a criterion for the basic suitability for electrocaloric cooling application, we directly measure the temperature change (DT) upon the application and withdrawal of an electric field as a function of the ambient temperature. For the undoped 0.92PMN-0.08PT bulk ceramics fabricated by the columbite route, we observed the maximum DT of 0.24 K when applying an electric field of 2 kv-rnm-1 at 28°C (DTup). Withdrawing the electric field at same conditions showed a temperature decrease of 0.20 K (DTdown). The resulting DTdown:DTup ratio is also considered.