Fig. 3.

Structure, electrical and mechanical properties of rGO films. a A large rGO film with a size of 30 × 10 cm². b A origami crane made by rGO film, showing very good flexibility. c Cross-sectional SEM image of a rGO film. Scale bar: 1 μm. d–g XRD patterns (d), the corresponding XRD peak position and FWHM (e), stress-strain curves (f) and electrical conductivities (g) of the rGO films prepared at different rotating rate using GO nanosheets with different lateral size (~1 μm and ~20 μm). h Electrical conductivity and tensile strength comparison of the rGO films prepared by CCC method and other methods^{22,31,35–39}. The size of the GO nanosheets used is shown for each case