Memory effects in chiral nematic liquid crystals doped with functionalised single-walled carbon nanotubes

Abstract

Octadecylamine-functionalised single-walled carbon nanotubes (SWCNTs) were dispersed into nematic liquid crystals (LCs) doped with chiral molecules. The collective orientation of nematic LC molecules in helical layers was manipulated by varying dopant concentration. Highly anisotropic nature of SWCNTs enhanced the anisotropy of the LC as confirmed by polarised fluorescence spectroscopy. The π-π interaction of SWCNTs present in the planar alignment layers and twisted nematic LC molecules affects the molecular relaxation process. An irreversible electro-optic memory in the material has been observed.

Dielectric properties of nematic liquid crystal with impurities of supramolecular Ni-TMTAA-TCNQ complexes

“…This dependence for the whole range of the studied temperatures correlates with the temperature dependence of the τ -1 -value. 4. It has been shown that the conductivity of the samples in both homeotropic and planar orientations of molecules changes according to the power law on the concentration of molecules up to the impurity concentration 1 wt.%.…”

“…It is certainly one of the triumphal accords of practical application of LC. In further studies of the LC properties, much of the scientific problems are based on the expansion of the LC functional properties due to the introduction of impurities of different types in them [1][2][3][4][5][6][7]. From our viewpoint, the capabilities of LC-based devices can be greatly expanded, if the impurities will absorb light in the spectral range visible for human eyes.…”

“…where α is the Cole-Cole parameter, the value which varies from 0 (Debye dispersion) to 1. The difference between the relaxation processes given by the relations (4) and (5) is that if in the case of the Debye dispersion, the dependence ε(ε) (Cole-Cole diagram) can be approximated by a semicircle, then in the case of the Cole-Cole dispersion the dependence ε(ε) has the form of an arc.…”

Индуцированный Магнитным Полем Ориентационный Переход В Геликоидальном Жидкокристаллическом Антиферромагнетике

“…Феррохолестерики привлекательны открывающейся в них возможностью посредством слабых внешних магнитных полей изменять спиральность образуемой структуры и, тем самым, легко модулировать спектральный состав отраженного света. Теоретические и экспериментальные исследования физических явлений в геликоидальных ФМ ЖК вызывают в последние годы большой научный интерес [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18].…”

Review—Surface Modification of Carbon Nanotubes: A Tool to Control Electrochemical Performance

“…sp 2 hybridized conjugation remains unaltered. Furthermore, these methods have also been proven efficient and economical, [1][2][3]6,8,9,[11][12][13][14][15][16][17]19,23,25,28,30,32,34,37,39,44,45,47,49,55 hence preferred. Mechanical dispersion methods involve stirring, sonication and calendaring.…”