Carbon dots regulate crosslinking of functionalized three-dimensional graphene networks decorated with p-phenylenediamine for superior performance flexible solid-state supercapacitors

Abstract

Abstract p-phenylenediamine (PPD) are preferred as a functional monomer to modify graphene oxide for functionalized three-dimensional (3D) graphene networks by a facile hydrothermal method, and carbon dots (CDs) served as fill factor to regulate the crosslinking degree for optimized functionalized 3D graphene networks (rGO-PPDs-CDs), which is in favor fast-moving of ions to achieve higher capacitance performance. As a result, rGO-PPDs-CDs exhibits promising potential as an activate electrode material in supercapacitor, revealing optimal specific capacitance (468.7 F/g at a current density of 0.5 A/g) and excellent rate capability (72.9% even up to high current density of 100 A/g). Furthermore, flexible solid-state SCs (FSSCs) explored using rGO-PPD-CDs, exhibit high specific capacitance (321.9 F/g at 0.5 A/g), and maximum specific energy of 10.99 Wh/kg and highest specific power of 10.09 kW/kg. In addition, FSSCs also maintain the original performance even in a harsh environment (bending state or twisting state). The excellent electrochemical performance of FSSCs based on rGO-PPD-CDs makes it an attractive candidate for energy-storage devices.