Large conventional and inverse electrocaloric effects in PbMg0.5W0.5O3 multilayer capacitors above and below the Neel temperature

Bulk PbMg0.5W0.5O3 (PMW) is an antiferroelectric in which an electric field of 12 V & mu;m(-1) is sufficient to initiate a nominally reversible transition to a dipole-aligned (ferroelectric) phase if operating just below the Neel temperature T (N), near room temperature (Li et al 2021 Adv. Funct. Mater. 31 2101176). Here we describe multilayer capacitors (MLCs) of PMW that permit 27 V & mu;m(-1) to be applied without breakdown. Below T (N), nominally reversible driving of the partial (full) antiferroelectric-ferroelectric (AF-FE) transition over a wide (narrow) range of temperatures yields large inverse electrocaloric (EC) effects that peak at & UDelta;T-j & SIM; -2.6 K when applying 25 V & mu;m(-1) at 293 K (& UDelta;T-j denotes directly measured temperature jumps). Above T (N), nominally reversible driving of the partial (full) paraelectric-ferroelectric (PE-FE) transition yields large conventional EC effects that peak at & UDelta;T-j & SIM; +5.2 K when applying 25 V & mu;m(-1) at 302 K. This good EC performance near room temperature implies that MLCs of PMW could be exploited in prototype EC coolers.

Automated summary

This study describes multilayer capacitors (MLCs) of PbMg0.5W0.5O3 (PMW) that can drive the partial antiferroelectric-ferroelectric (AF-FE) transition below the neutral temperature and the partial ferroelectric-ferroelectric (PE-FE) transition near room temperature. The PMW material exhibits good electrocaloric performance near room temperature, indicating its potential use in prototype electrocaloric coolers.