Self‐Assembly and Adjustable Ion Conducting Behavior of Graphene Oxide Liquid Crystalline Network Membranes

Abstract

Abstract Self‐assembly of graphene oxide liquid crystalline network (GO‐LCNs) membranes is constructed for the first time via Langmuir–Blodgett assembly technique. The GO‐LCNs are synthesized by hydrogen‐bonded self‐assembly between carboxyl groups on graphene oxide and pyridinyl groups on liquid crystalline polymers. These GO‐LCNs membranes possess distinct microstructures and show adjustable ion conducting behavior due to GO planar structure induced by mesogen oriention of liquid crystal molecules. The liquid crystalline behavior of the GO‐LCNs is identified by combining polarized optical microscopy, differential scanning calorimetry, and X‐ray diffraction measurements. The liquid crystalline properties of GO‐LCNs are adjusted by the composition of the liquid‐crystalline polymers. The microstructures and ion conducting behavior of GO‐LCNs membranes are investigated by applying different electromagnetic field, which are identified by different ionic conductivity of lithium bis(trifluoromethanesulphonyl)imide organic solution passed through the membranes. Ionic conductivity of solutions is increased nearly 100‐fold and tenfold for an orientated GO‐LCNs membrane. These GO‐LCNs are promising materials in numerous applications such as high‐performance electrode material, ion battery materials, proton conductors, and so on.

Keywords

• graphene oxide
• liquid crystalline polymers
• self‐assembly