Large‐Area, Ultrathin Inorganic Network Coverages–Graphene Hierarchical Electrodes for Flexible, Heat‐Resistant Energy Storage Application

Abstract

Graphene and quasi‐2D graphene‐like materials with an ultrathin thickness have been investigated as a new class of nanoscale materials due to their distinctive properties. A novel “molecular tools‐assistances” strategy is developed to fabricate two kinds of graphene‐based electrodes, ultrathin Fe‐doped MnO2 network coverage–graphene composites (G‐MFO) and ultrathin MoS2 network coverage–graphene composites (G‐MoS2) with special hierarchical structures. Such structures enable a large contact interface between the active materials and graphene and thus fully exploit the synergistic effect from both the high specific capacitance of MFO or MoS2 and the superb conductivity of graphene. Benefiting from their unique structural features, G‐MFO and G‐MoS2 films directly use as free‐standing electrodes for flexible asymmetric supercapacitors with a nonaqueous gel electrolyte. The device achieves a high energy/power density, superior flexibility, good rate capability as well as outstanding performance stability even at a high temperature. This work represents a promising prototype to design new generation of hybrid supercapacitors for future energy storage devices.