Hierarchical xanthan gum/graphene oxide nanocomposite film induced by ferric ions coordination

Light-weight and high-performance nanocomposites that contain reinforcements with preferred orientation have attracted significant attention. Here, a hierarchical, lightweight, and nacre-like graphene oxide (GO) and xanthan gum (XG) nanocomposite film was fabricated via a simple, rapid, economic, and green method. Graphene oxide and xanthan gum were used in making of "bricks and mortar" and forced to self-assemble into GO/XG-Fe(III) hydrogel via ferric ions coordination. Oriented and hierarchical GO/XG-Fe(III) nanocomposite film was obtained by drying the hydrogel. Due to the well-defined hierarchical structure and coordination bond, the GO/XG-Fe(III) nanocomposite film exhibited high strength of 93.6 ± 3.82 MPa. Accompanied by the mechanical strength, specific thermal conductivity on the parallel and perpendicular direction was obtained due to the anisotropy of the GO nanosheets in the nanocomposite film. Furthermore, the stability of the GO/XG-Fe(III) nanocomposite film against various organic solvents and acidic solution was demonstrated. It may enable these materials to be used in aerospace, electronic devices, biological membranes and scaffolds.