Self-assembled hierarchical porous nanoarchitectured 2,6-diaminopyridine decorated N-doped reduced graphene oxide as advanced electrode for high-performance aqueous Zn-ion hybrid supercapacitors

Abstract

2,6-diaminopyridine (DAP), an active organic molecule containing amino groups and pyridine N is expected to be an attractive material for energy storage due to its fast and reversible proton-involved redox activity. Herein, the novel N-doped (or CNTs) and DAP organic molecules double-modified reduced graphene oxide nanocomposites with hierarchical porous nanoarchitectures were successfully designed and synthesized by a simple solvothermal method. Benefiting from the advantages of the three components and the positive synergistic enhancement between them, the newly synthesized N-RGO/DAP and CNTs/RGO/DAP nanocomposites exhibit excellent electrochemical properties, such as high specific capacitance, excellent rate capability and cycling stability. Furthermore, the Zn-ion hybrid supercapacitor further assembled with the optimal N-RGO/DAP as cathode delivers excellent Zn-ion energy storage performance in aqueous electrolyte, with a high specific capacitance (capacity) of 320.2 F g−1 (158.3 mAh g−1), excellent energy density of 140.9 Wh kg−1 at a power density of 534 W kg−1, and an ultra-long durability of 95.3% capacitance retention after 16,000 cycles at a large current of 100 mV s−1. This paper provides a novel strategy and advanced electrode nanocomposite with excellent electrochemical properties, which shows great promise in high-performance energy storage devices with high-flexibility, light-weight and sustainability.