Polypyrrole@TEMPO-oxidized bacterial cellulose/reduced graphene oxide macrofibers for flexible all-solid-state supercapacitors

The emerging fiber-based supercapacitors with high energy and power density are highly desirable for they provide strong support for the development of portable and wearable devices. Here, a flexible, binder-free highperformance fiber-based supercapacitors is structured based on hierarchical polypyrrole@TEMPO-oxidized bacterial cellulose/reduced graphene oxide macrofibers by wet spinning and in situ polymerization polypyrrole. For the synergistic effects of three components, the excellent specific capacitance of the electrode with 391 F g(-1) (373 F cm(-3)) at the current density of 0.5 A g(-1) (0.48 A cm(-3)) and the fiber-based supercapacitor made of the electrodes with 259 F g(-1) (258 F cm(-3)) at the current density of 0.2 A g(-1) (0.199 A cm(-3)) are achieved. Moreover, the fiber-based supercapacitor exhibits a high energy density of 8.8 mWh cm(-3) at the power density of 49.2 mW cm(-3) and a highpower density of 429.3 mW cm(-3) at the energy density of 4.1 mWh cm(-3), which is better than most previously reported graphene fiber-based supercapacitors. In these devices, we realize a desirable combination of excellent electrochemical performance and good flexibility, which will be significant for satisfying the requirement of the energy and power in various portable, miniaturized, and wearable electronic devices.