Pyroelectric effect enhancement through product property under open circuit condition

Abstract

An analytical model for the pyroelectric ͑PY͒ effect under open circuit condition and 2-2 connectivity laminates of various pairs of PY and nonpyroelectric ͑NP͒/elastic materials has been developed. It is evident from our analysis that there indeed is a substantial dissimilarity between the PY coefficients and figure of merit for efficiency for various PY-NP pairs under short circuit and open circuit conditions. We believe this implies that there should be a greater distinction made between the PY coefficients under these two electrical conditions than previously thought. The indicators for various PY-NP material pairs that can be utilized to determine their PY coefficient enhancement potential under open circuit condition have been identified. The investigated PY materials are lead zirconate titanate ͑PZT-5H and PZT-5A͒, barium titanate, lithium tantalate, lithium niobate, and polyvinylidene fluoride ͑PVDF͒, while the NP materials are stainless steel, polytetrafluoroethylene ͑PTFE or Teflon͒, chlorinated polyvinyl chloride thermoplastic ͑CPVC͒, aluminum, zinc, and Invar 36. Extraordinarily large PY coefficient of 97ϫ 10 −4 C m −2 K −1 at minimum thickness ratio R min is expected for PZT-5H-CPVC pair while PVDF-CPVC could show increase in the secondary PY coefficient of up to 350%. In addition, where the figure of merit for efficiency is concerned, for the same volume of the composite PZT-5A-PTFE pair it reaches 24, a 24-fold increase in efficiency at R min. Our analysis techniques should provide a methodological way for appraising the potentials of particular PY material and its 2-2 laminates for applications under open circuit condition such as PY X-ray generation, electron accelerator, and nuclear fusion.

Graphene Ink Laminate Structures on Poly(vinylidene difluoride) (PVDF) for Pyroelectric Thermal Energy Harvesting and Waste Heat Recovery

“…12 Despite the thin nature of the metallic electrodes, compared to the pyroelectric active material, it is thought that the shear stress that is developed between the laminate layers significantly contribute to the thermal energy conversion. 13 In contrast, it is reported in the literature that the pyroelectric response with proportionally thick laminates gradually improves to an optimum for equally thick pyroelectric and nonpyroelectric layers. 14 In this paper, asymmetric screen-printed thick film black graphene ink electrodes on PVDF are studied for pyroelectric harvesting.…”

“…As the electrode thickness decreases, the mechanical strain due to a thermal expansion mismatch improves the pyroelectric coefficient by up to 100 % under open and closed circuit conditions 12 . Despite the thin nature of the metallic electrodes, compared to the pyroelectric active material, it is thought that the shear stress that is developed between the laminate layers significantly contribute to the thermal energy conversion 13 . In contrast, it is reported in the literature that the pyroelectric response with proportionally thick laminates gradually improves to an optimum for equally thick pyroelectric and non-pyroelectric layers 14 .…”

Temperature dependent structural, elastic, and polar properties of ferroelectric polyvinylidene fluoride (PVDF) and trifluoroethylene (TrFE) copolymers

“…6, which are presumably made for not fully crystalline and defect-free samples, also appear higher than the polarization values produced by this FF. 64,65 While we predict smaller pyroelectric coefficients in poly(VDF-co-TrFE) copolymer crystals, this declining trend is not monotonous, displaying a relatively large pyroelectric response in the 70/30 system. Therefore, the presented results demonstrate that in order to correctly simulate the polarization in such systems a successful FF parameterization (e.g., such as the one introduced for PVDF in Ref.…”

Thermomechanical Responses and Energy Conversion Efficiency of a Hybrid Thermoelectric–Piezoelectric Layered Structure

“…The elastic modulus and coefficient of thermal expansion are from Tsai et al [20] and Chen et al [21], respectively. The piezoelectric material is PZT-5H with the properties listed in Table 2 [22][23][24]. The temperatures at the cold and hot ends of the hybrid structure are Θ c = 290 K and Θ h = 330 K, respectively.…”