Preparation of high-performance graphene materials by adjusting internal micro-channels using a combined electrospray/electrospinning technique

The reduced graphene oxide (rGO) based macroscopic materials show good application potential in many fields because it forms a conductive network with a high specific surface area. However, how to further improve its performance is still the primary problem restricting its practical application. In this study, the composite film of GO flakes and nylon fibers was prepared through the combination of electrospinning and electrospray technology at first. Along with the reduction of the GO flakes and disintegration of nylon fibers during the thermal reduction process, the rGO-based macroscopic material with internal micro-channels (GIMC) was successfully prepared. Because the number and size of internal channels are determined by the content and diameter of nylon fiber, it is convenient to control the properties of GIMC by using this preparation method, especially the specific surface area and pore size distribution. The optimized GIMC sample has excellent performance in the field of secondary batteries (1257.0 mAh g ⁻¹ at a current density of 0.5 A g ⁻¹ ) and supercapacitors (185 F·g ⁻¹ at a current density of 0.5 A g ⁻¹ ). In addition, the interpenetrating channels inside the GIMC can provide paths and reaction spaces for other functional materials. Based on this, the GIMC/ polyaniline (PANI) composite was successfully prepared by in-situ polymerization. The supercapacitor device based on the GIMC/PANI shows excellent rate performance and cycle performance. It has a specific capacitance of up to 892 F g ⁻¹ at a current density of 0.5 A g ⁻¹. This provides a new strategy for the preparation of graphene-based high-functional composites and lays a foundation for the expansion of its applications.