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 MnO 2 network coverage–graphene composites (G‐MFO) and ultrathin MoS 2 network coverage–graphene composites (G‐MoS 2 ) 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 MoS 2 and the superb conductivity of graphene. Benefiting from their unique structural features, G‐MFO and G‐MoS 2 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.