Functionalization of partially reduced graphene oxide hydrogels with 2-Aminopyridine for high-performance symmetric supercapacitors

In this work, 2-Aminopyridine functionalized partially reduced graphene oxide hydrogels (APGHs) have been prepared via a simple hydrothermal method. During the reaction process, graphene oxide was used as the reactant and 2-Aminopyridine was used as both reductant and N dopant. Furthermore, pyridine ring can not only act as a spacer to prevent the restacking of graphene sheets, but also enhance the pseudocapacitance of the material through its redox activity. The characterization results showed that APGHs possessed high content of heteroatom functional groups (N, O), high surface area and 3D interconnected structure, respectively. Thus, the assembled APGH-40-based symmetric supercapacitor delivers a high-specific capacitance of 266.7 F g−1 at 0.3 A g−1, even at 10 A g−1, this value can still maintain at f 215.9 F g−1. In addition, the device also possesses a high energy density (9.3 Wh kg−1 at 75.0 W kg−1) and outstanding capacitance retention of 102.9% after 10,000 cycles at 10 A g−1. Therefore, the synthesized APGHs display a promising prospect in supercapacitor application.