Fast response in TN liquid-crystal cells: effect of functionalised carbon nanotubes. Issue 4 (15th March 2016)

• Record Type: Journal Article
• Authors: Kumar, Jitendra; Manjuladevi, V.; Gupta, R.K.; Kumar, S.
• Is Part Of: Liquid crystals. Volume 43:Issue 4(2016)
• Page Start: 488
• Page End: 496
• Publication Date: 2016-03-15
• Subjects: Nematic liquid crystals -- functionalised single-walled CNT -- twisted alignment mode -- electro-optic response time; Liquid crystals -- Periodicals; 548.905
• DOI: 10.1080/02678292.2015.1119320
• Languages: English
• ISSNs: 0267-8292

Abstract

ABSTRACT: The optical response time of a nematic liquid crystal (NLC) decreases due to incorporation of carbon nanotubes (CNTs) in the liquid-crystal host. Such reduction is believed to be due to an increase in the elastic constant of the nanotube-doped LC system. In this paper, we present the effect on optical response due to doping an NLC with octadecylamine functionalised single-walled carbon nanotubes (ODA-SWCNT) in a twisted alignment mode. The electro-optic switching amplitude of ODA-SWCNT nanocomposites of NLC decreases compared to pure NLC. A fast response time is observed with an increase in the concentration of ODA-SWCNT in NLC host. Additionally, optical response of pure NLC in a twisted nematic (TN) cell fabricated using mixtures of polyimide (PI) and ODA-SWCNT as an alignment layer is investigated. The optical response time decreased by ~75% in a TN cell fabricated with a mixture of PI and ODA-SWCNT compared to that of a TN cell prepared using a pure PI alignment layer. The presence of ODA-SWCNT in the alignment layer enhances the surface anchoring of the NLC molecules leading to an increase in the elastic constant and a decrease in the optical response time of NLC. GRAPHICAL ABSTRACT: