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 (La
³⁺
, Bi
³⁺
, Eu
³⁺
, Nd
³⁺
, Y
³⁺
, Cr
³⁺
) and charge equivalent dopants (Sr
²⁺
, Co
²⁺
, Mn
²⁺
, Ta
⁵⁺
) on the dielectric and ferroelectric behavior of 0.92 Pb(Mg
_1/3
Nb
_2/3
)O
₃
-0.08 PbTiO
₃
(0.92PMN-0.08PT). As a criterion for the basic suitability for electrocaloric cooling application, we directly measure the temperature change (ΔT) 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 ΔT of 0.24 K when applying an electric field of 2 kv-rnm
^-1
at 28°C (ΔT
_up
). Withdrawing the electric field at same conditions showed a temperature decrease of 0.20 K (ΔT
_down
). The resulting ΔT
_down
:ΔT
_up
ratio is also considered.