Constructing N-doped and 3D Hierarchical Porous graphene nanofoam by plasma activation for supercapacitor and Zn ion capacitor

Traditional electrode materials still face vital challenges of few active sites, low porosity, complex synthesis process, and low specific capacitance. Herein, N-doped and 3D hierarchical porous graphene nanofoam (N-GNF) is created on car-bon fibers (CFs) by employing a facile, fast, and environmentally friendly strategy of N-2 plasma activation. After an appropriated N-2 plasma activation, the graphene nanosheets (GNSs) synthesized by Ar/CH4 plasma deposition transform into N-GNF successfully. N doping donates rich active sites and increases the hydro-philia, while hierarchical nanoarchitecture exposes an enlarged effective contact area at the interface between electrode and electrolyte and affords sufficient space for accommodating more electrolytes. The as-assembled flexible N-GNF@CFs//Zn NSs@CFs Zn ion capacitor delivered a high energy density of 105.2 Wh kg(-1) at 378.6 W kg(-1) and initial capacity retention of 87.9% at the current of 2 A g(-1) after a long cycle of 10,000.

Automated summary

N-doped and 3D hierarchical porous graphene nanofoam (N-GNF) is created on carbon fibers (CFs) via a facile and environmentally friendly N-2 plasma activation method. The N doping increases active sites and hydrophilicity, while the hierarchical nanoarchitecture enhances the effective contact area and electrolyte accommodation. The assembled N-GNF@CFs//Zn NSs@CFs zinc ion capacitor exhibits a high energy density of 105.2 Wh kg(-1) at 378.6 W kg(-1) and an initial capacity retention of 87.9% at 2 A g(-1) after 10,000 cycles.