Pyroelectric figure of merit in alternating hemicyanine/NC Langmuir–Blodgett films incorporating barium ions

Abstract

Pyroelectric properties in alternating hemicyanine (DAEP)/nitrogencrown (NC) Langmuir–Blodgett (LB) films and effects of incorporating barium cations on pyroelectric behaviors have been investigated. Its pyroelectric coefficient measured is found to be 58 μC m −2 K −1at 300 K. Their dielectric properties have been measured and used to determine the figures of merit in thermal devices. Relative permittivity ( ɛ r) and dielectric loss values (tan δ) of pyroelectric films (in the range of 1–100 KHz) are found to be 2.34–1.96 and 0.08–0.04, respectively. These data give a maximum pyroelectric figure of merit of 150 μC m −2 K −1 in the alternating LB films incorporating barium ions. The effects of different deposition on pyroelectric properties are also discussed in this paper.