Electrically conductive and mechanically strong biomimetic chitosan/reduced graphene oxide composite films

Composite films of chitosan and reduced graphene oxide (RGO) sheets with nacre-like layered structure have been prepared by vacuum filtration of the stable aqueous mixture of both components. The film containing 6 wt% RGO is electrically conductive with a conductivity of 1.2 S m(-1). Furthermore, it is mechanically strong and ductile; its Young's modulus, tensile strength and elongation at break were measured to be 6.3 +/- 0.2 GPa, 206 +/- 6 MPa and 6.5 +/- 0.6%, respectively. These values partly exceed those of nacre. The high mechanical and electrical properties of chitosan/RGO composite films are mainly attributed to the uniform dispersion of RGO nanofillers in the polymer matrices to form a compact layered structure.