Microscopic Structure Analysis of Graphene Oxide Liquid Crystals under Shear

Abstract

Graphene oxide (GO) can be easily dispersed in water and form nematic liquid crystals (LC) and GO LC has been actively used in solution processing of high performance graphene-based fibers. In these applications, high shear stress is necessarily exerted to GO suspension, which affects the structure and alignment of GO and thus resulting properties. However, the detailed characterization of microstructure and property of GO under shear is difficult to probe and thus remain challenged. Here, we examine the microstructure of GO LC under various shear condition and correlate it with rheological properties employing extensive Rheo-small angle X-ray scattering (Rheo-SAXS). Rheo-SAXS enables a simultaneous investigation of structure-property of GO suspension, providing more detailed information such as LC deformation under shear. We believe that this study can widen the fundamental understandings towards GO suspensions under shear and suggest processing conditions for GO based applications.