Orientational ordering of polydisperse nanorods on a flat surface

Abstract

The use of two-dimensional liquid crystals (2D LCs) made of carbon nanorods has become increasingly popular in electronic, optical, and energy applications due to their unique properties. However, the orientational ordering of such liquid crystals remains poorly understood. Here, we model of 2D LCs using the length polydisperse hard needle model and apply theOnsager theory to explore the impact of length polydispersity on nematic ordering. Our results show that length polydispersity plays a crucial rolein stabilizing the nematic phase over the isotropic phase, albeit at the expense of weaker orientational ordering. Longer rods, in particular, contribute to the stabilization of the nematic phase, whereas shorter rods result in weaker nematic ordering. To achieve a highly ordered 2D nematic phase, the polydispersity of the nanorods must be reduced.