Liquid crystals: Electric fields line up graphene oxide

Abstract

Jang-Kun Song and colleagues demonstrate that efficient electric field switching of graphene oxide (GO) liquid crystals is indeed possible in low-concentration dispersions and demonstrate a prototype of a GO LCD. Song and collaborators observed that flow or high-frequency alternating-current electric fields induced liquid crystallinity in GO dispersions at concentrations low enough for the dispersion to be isotropic when the field is off. The electric-field switching of GO liquid crystals demonstrated by Song and co-authors occurs through a direct transition from an isotropic to a highly aligned liquid crystalline phase. Another notable point of Song and co-authors' GO LCDs is their low power consumption for optical switching. GO flakes with larger Kerr coefficients would lead to faster relaxation times, of relevance to applications in optical communication, nonlinear optics and laser technology. GO liquid crystals also have prospects for the fabrication of functional materials with tailored morphologies.