The pyroelectric properties of La0.03Sr0.255Ba0.7Nb2-yTiyO(6-y/2) (LSBNT) ceramic pellets using several Ti/Nb ratios sintered at 1250°C for 5 h were investigated. The samples were subjected to several values of electric fields in order to obtain the optimum electric field strength. The pyroelectric coefficients, (p) were measured using the quasi-static method by applying several heating rates. The results show that the Ti/Nb ratios and the dc poling field, (Edc) influenced the measured pyroelectric coefficient of the LSBNT ceramic pellets. The mean grain size of the particles as obtained from scanning electron microscope (SEM) does not seem to give significant impact on the pyroelectric coefficient of the ceramic pellets. However, the X-Ray diffraction (XRD) results indicate that the crystallite sizes of Ti and Nb of these ceramic pellets after being treated with sintering process also influence the measured pyroelectric coefficients of the ceramic pellets.
Spin coated polyvinlylidenefluoride-trifluoroetylene (PVDF-TrFE 70/30mol%) copolymer thin film were initially produced and annealed at varying temperatures (100°C to 160°C). The morphology, dielectric and ferroelectric analysis showed that PVDF-TrFE film annealed at 120°C produced the highest remnant polarization, Pr of 92 mC/m2, with orderly and grain-like shaped crystallites. The filled PVDF-TrFE, loaded with various volume percentages (1 – 7%) of Magnesium Oxide (MgO) nanofillers and then, annealed at 120°C, produced homogenous filler distribution with low agglomerates, especially for 3% PVDF-TrFE filled films. Moreover, the annealed PVDF TrFE/MgO(3%) generated the highest value of Pr in comparison to the other filled nanocomposite thin films. Most importantly, the saturation of hysteresis loop, Ps for annealed PVDF-TrFE/MgO(3%) film was relatively improved by 20% as compared to the unfilled annealed thin film. This study established that, 3% MgO loaded in PVDF-TrFE thin film and annealed at 120 °C demonstrated a stable ferroelectric thin film, closed to an ideal ferroelectric film, in which the ratio Pr/Ps for the film established a value approaching unity (value of 1).