A TGS/70:30 VDF:TrFE copolymer composite: Thin film formation and pyroelectric properties

Thin pyroelectric composite films have been fabricated in which both phases are electroactive. Triglycine sulphate crystals, grown by freezing an aqueous solution at various rates and freeze-drying the resultant solid mass, were mixed (10% w/w) with a solution of 70:30 vinylidene fluoride:trifluoroethylene copolymer in butanone and films were produced by spin-coating. The best material possessed a pyroelectric coefficient of (60 ± 2) μCm-2 K-1 and a figure of merit (pyroelectric coefficient/✓ (relative permittivity × dielectric loss)) of 150 μCm-2 K-1, some 18% and 35% larger, respectively, than the corresponding values for the copolymer alone. Keywords: TGS70:30 VDF:TrFE copolymercompositepyroelectricity Notes Department of Physics, Loughborough University of Technology, Loughborough, Leicestershire, UK Department of Chemistry, University of Portsmouth, Portsmouth, Pol 2DT, UK