Characterization of Langmuir-Blodgett films of arachidic acid and 1,2-bis(dodecyloxy)-4,5-diaminobenzene in pyroelectric devices

Abstract

Non-centrosymmetric materials exhibiting a temperature-dependent electric polarisation are known as pyroelectrics. It is well known that the tilt mechanism and the proton transfer between acid-amine interactions play an important role for the pyroelectric effect in alternate layer Langmuir-Blodgett (LB) films. In this work arachidic acid (AA) has been deposited alternately with 1,2-bis(dodecyloxy)-4,5-diaminobenzene (DADB) using the LB film deposition technique to form multilayered LB films. Pyroelectric and dielectric measurements have been performed for different layered AA/DADB films. Pyroelectric coefficients for this LB film system have been obtained using a quasi-static measurement system. Dielectric measurements have been used to determine the relative permittivity and dielectric loss tangent. The data obtained from pyroelectric and dielectric measurements have been used to calculate the figure of merit for these LB films which has the average value of 6.34 mu C m(-2) K-1. (c) 2006 Elsevier B.V. All rights reserved.