Pyroelectric effect in Langmuir-Blodgett films incorporating ions

Abstract

Non-centrosymmetric materials exhibiting a temperature-dependent electric polarisation are known as pyroelectrics. It is well known that the tilting mechanism and proton transfer between acid/amine interactions play an important role for the pyroelectric effect in alternate layer Langmuir-Blodgett (LB) films. In this work, the ionic mechanism is investigated using copolysiloxane/eicosylamine alternate layer LB films incorporating different metallic cations such as cadmium, barium and manganese. Pyroelectric coefficients of these LB films are measured at several temperatures and the dielectric constant and dielectric losses are obtained using a dielectric measurement system. The figure of merit of these LB film assemblies shows the highest figure of merit for alternate layer LB films. (C) 2004 Elsevier B.V. All rights reserved.