Effect of functionalisation of carbon nanotubes on the dielectric and electro-optical properties of ferroelectric liquid crystal

Abstract

We present the results based on dielectric, electro-optical and photoluminescence (PL) measurements of a ferroelectric liquid crystal (FLC) doped with differently functionalised (–COOH, –OH and –NH₂ groups) multi-walled carbon nanotubes (MWCNTs). Functional group induced significant modifications in the dielectric permittivity (ε′), dielectric loss factor (tan δ), PL intensity and material parameters of MWCNT/FLC composites have been observed. We found that MWCNTs functionalised with –OH and –NH₂ have enhanced the dielectric properties and the PL intensity of FLC material remarkably. The observed results have been explained on the basis of the interaction between FLC material and functionalised MWCNTs. The present study is our sincere attempt to understand the effect of functionalisation of MWCNTs on the FLC properties.

Keywords:

• ferroelectric liquid crystal
• carbon nanotubes
• photoluminescence

Acknowledgements

The authors sincerely thank Professor R. C. Budhani, Director, CSIR–National Physical Laboratory, New Delhi, for his interest in this work. P.G. is grateful to the Council of Scientific and Industrial Research (CSIR), India, for supporting this work under research fellowship scheme: HRDG/CSIR-Nehru PDF/PS/EMR-I/01/2011 and S.T. is thankful to CSIR for providing financial assistance.