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

Abstract

Abstract Bulk PbMg0.5W0.5O3 (PMW) is an antiferroelectric in which an electric field of 12 V μm−1 is sufficient to initiate a nominally reversible transition to a dipole-aligned (ferroelectric) phase if operating just below the Néel 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 µm−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 ΔTj ∼ –2.6 K when applying 25 V μm−1 at 293 K (ΔTj 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 ΔTj ∼ +5.2 K when applying 25 V μm−1 at 302 K. This good EC performance near room temperature implies that MLCs of PMW could be exploited in prototype EC coolers.