An Eco-Friendly, Nanocellulose/RGO/in Situ Formed Polyaniline for Flexible and Free-Standing Supercapacitors

Abstract

There have been extensive demands for eco-friendly, lightweight, flexible, and high performance supercapacitors for advanced applications like wearable electronics, hybrid electric vehicles, and industrial grid storage. In this work, a metalless nanocellulose-based PANI/RGO electrode with excellent flexibility, mechanical strength, and conductivity was developed and assembled into sandwich-like supercapacitors. Reduced graphene oxide (RGO) was mixed into aniline during the in situ polymerization of PANI to improve conductivity of the composite electrode. This eco-friendly metalless nanocellulose based electrode was fabricated via filtrations driven by a vacuum and assembled into sandwich structures. The ratios between nanocellulose, PANI, and RGO were optimized to achieve both high electrochemical performance and good mechanical properties. The composite electrode has a large active materials mass loading ratio of 16.5 mg/cm2, and the assembled supercapacitor gives small impedance at 3.90 Ω, suggesting an excellent conductivity. This work shows the great potential of developed flexible and lightweight nanocellulose composites in the fabrication of supercapacitors that can be used in a variety of biomedical applications including e-skins.