Khan, Sidra and Chauhan, Shikha and Chandran, Achu and Czerwinski, Michal and Herman, Jakub and Biradar, Ashok M. and Prakash, Jai (2019) Enhancement of dielectric and electro-optical parameters of a newly prepared ferroelectric liquid crystal mixture by dispersing nano-sized copper oxide. Liquid Crystals , 47 (2). pp. 263-272. ISSN 0267-8292

PDF - Published Version Restricted to Registered users only Download (1878Kb) | Request a copy

Abstract

Here, we present the effect of copper (II) oxide nanoparticles (nCuO) on dielectric and electro-optical parameters of a newly prepared ferroelectric liquid crystal (FLC) mixture, namely W302. The FLC mixture, comprising of pyrimidine compounds, was characterised through dielectric spectroscopy, differential scanning calorimetry (DSC), polarising optical microscopy (POM) and other electro-optical methods. The material parameters such as spontaneous polarisation, rotational viscosity, response time and tilt angle of W302 were found to be 14 nC/cm(2), 240 mPa.s, 150 mu s and 28(& x1d3c;), respectively. The phase transition temperatures of W302 were observed through DSC and further confirmed by the dependence of dielectric loss factor in homogeneously aligned FLC sample with temperature. We also demonstrate the observance of a low-frequency dielectric relaxation mode due to the unwinding of the helix, called as partially unwound helical mode (p-UHM) along with Goldstone mode. The behaviour of p-UHM has been systematically studied with temperature and applied bias field. Further, dispersion of nCuO into host W302 has shown a significant increase in dielectric permittivity. Also, the p-UHM relaxation peak in the dielectric regime has disappeared with the incorporation of nCuO. These studies would be useful to fabricate better electro-optical devices for display, switching and beam steering applications. The formulation and characterization of a ferroelectric liquid crystal (FLC) mixture W302 composed of pyrimidine compounds is presented. Then, we observed the effect of copper (II) oxide nanoparticles (nCuO) on dielectric and electro-optical parameters of a newly prepared and characterized FLC mixture.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/s Taylor & Francis.
Subjects:	Chemistry Crystallography Materials Science
Divisions:	UNSPECIFIED
Depositing User:	Mr. Yogesh Joshi
Date Deposited:	06 Mar 2020 10:07
Last Modified:	06 Mar 2020 10:07
URI:	http://npl.csircentral.net/id/eprint/4187

Actions (login required)

View Item