Hybrid films composed of reduced graphene oxide and polypyrrole-derived nitrogen-doped carbon nanotubes for flexible supercapacitors

Abstract

Electrode materials for flexible supercapacitors possessing exceptional and maintaining electrical properties have garnered significant attention in academic research. The graphene oxide (GO) and polypyrrole-derived nitrogen-doped carbon nanotubes (N-CNTs) were mixed to obtain a GO/N-CNTs film. The GO/N-CNTs film was then reduced to prepare a flexible reduced GO (rGO)/N-CNTs film. The specific capacitance of the rGO/N-CNTs film electrode was 223.2 F g−1 at a current density of 0.5 A g−1. The rGO/N-CNTs supercapacitor exhibited a specific capacitance of 130 F g−1 and energy density of 18.04 Wh·kg−1 at a current density of 0.5 A g−1. Furthermore, the capacitance retention of the supercapacitor was 68.7 % when the current density increased to 20 A g−1. In addition, the cyclic voltammetry test indicated that the capacitance retention of the supercapacitor remained at 82.7 % after 8000 cycles, and the capacitance retention still reached 70 % even after bending 600 times. The present study successfully presented the remarkable electrical characteristics of supercapacitors based on rGO/N-CNTs films. Additionally, the investigation has highlighted the noteworthy flexibility of supercapacitors, a feature of considerable significance for applications in wearable technology, portable electronic devices, and flexible displays.