Reduced graphene oxide-linked stacked polymer forests for highenergy-density supercapacitor

Hierarchical nanostructured materials consisting of stacked polymer nanowires forests interconnected by monolayer graphene sheets were fabricated through bottom-up nanofabrication. Driven by external voltage, aniline molecules and graphene oxide were alternatively assembled for hierarchical porous stacked nanostructures while graphene oxide was in-situ reduced to graphene during the assembly process. Scanning electron microscopy and atomic force microscope results indicated that monolayer graphene sheets served as the transition nodes for the neighboring nanowire arrays. As-produced hierarchical nanostructures were used as supercapacitor electrodes, and stack-dependent device properties were discovered. In the organic electrolyte, specific energy density was increased and power density was maintained as the stack of forests increased at each scan rate. The specific energy density of as-produced supercapacitors was as high as 137 Wh/Kg while the power density was 1980 W/Kg. Further ana