Evolution of morphology and electrochemical properties of colloidal nematic liquid crystal doped with carbon nanotubes and magnetite

摘要

In this study, evolution of single wall carbon nanotube (SWCNT) structure in E-7CN7 nematic liquid crystals (NLCs) and also the electrophysical characteristics of a mixture of the NLCs doped with SWCNT were investigated in the concentration range between 0.25 and 1 wt%. The measurements were carried out in sandwich cells with transparent electrodes, and electric field applied out-of-plane, i.e., perpendicularly to the cells. The results of the carbon nanotube structure changing caused by increasing concentration, can be considered into two regions: (1) branch aggregations in concentrations below 0.5 wt%, (2) percolation network in the concentration range between 0.5 and 1 wt%. In the first region, conductivity decreases while in the second one, it significantly increases. Magnetic properties were induced in E-5cN7 NLC using the Fe3O4 nanoparticles functionalized-CNT, which does not result in a significant impact on the LC's conductivity. Additionally, it is observed that SWCNT functionalization gives rise to changing in its structure in the LC medium and percolation network return into small aggregations in 1%wt. (C) 2019 Elsevier B.V. All rights reserved.