Tailoring the piezoelectric and electrocaloric response of nanocomposites based on poly (vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) with barium strontium titanate ceramic particles

Solid-state electrocaloric (EC) devices based on ferroelectric composites are the best choice when taking into account the energy supply requirements for environmental conditioning and refrigeration in buildings that rely on refrigeration systems, in order to reduce energy consumption and environmental impact of current systems. This work reports on the electrocaloric response of ferroelectric poly (vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene), P(VDF-TrFE-CTFE), composited with barium strontium titanate (BST) ceramic particles. The dielectric, piezoelectric and electrocaloric response of the solvent cased composite films can be tailored by ceramic particles content up to 40 wt%. The morphology, polymer phase, and thermal properties remain unaffected by the ceramic filler content. The dielectric constant increases significantly with increasing filler content, with the composite containing 40 wt% of ceramic particles showing the largest dielectric constant, ε' = 82 at 1 kHz. The piezoelectricity of all films has been demonstrated. The electrocaloric response also depends on BST content, the composite with BST content up to 20 wt% showing a maximum temperature change of 6 K at around 310 K (37 °C) under a field of 400 kV/cm. This work demonstrates the suitability of the developed composites for EC devices. • Ferroelectric composites based on P(VDF-TrFE-CFTE) and BST nanoparticles have been processed by solvent casting. • Piezoelectricity and ferroelectricity of the composites has been demonstrated for all composites. • A high electrocaloric effect has been obtained for the nanocomposites. • A maximum ΔT of 6 K at around 310 K under a field of 400 kV/cm has been obtained for the sample with a 20 wt% BST content.