Cellulose nanofibers/multi-walled carbon nanotube nanohybrid aerogel for all-solid-state flexible supercapacitors

In recent years, much effort has been dedicated to achieve environmentally friendly, low cost, and excellent performance energy storage devices. In this work, cellulose nanofibers (CNFs)/multi-walled carbon nanotubes (MWCNTs) hybrid aerogels are prepared from CNFs/MWCNTs hydrogels by supercritical CO₂ drying using CNFs as an effective, environmentally friendly, and steady dispersant of MWCNTs. All-solid-state flexible supercapacitors are fabricated using CNFs/MWCNTs hybrid aerogel film as the electrode material and charge collector. One-dimensional CNFs can effectively prevent the aggregation of MWCNTs, significantly enhance the re-wettability, and improve the utilization efficiency of the mesopores. Therefore, CNFs/MWCNTs hybrid aerogel film-based all-solid-state flexible supercapacitors exhibit excellent electrochemical properties: the specific capacitance is about 178 F g^-1. The flexible supercapacitors also exhibit excellent cyclic stability. Our work provides a novel method using low cost, and environmentally friendly CNFs to realize the full potential of the MWCNTs in an assembled bulk form. Taking its low cost and environmentally friendliness, CNFs/MWCNTs hybrid aerogel has great potential as the electrode material for all-solid-state flexible supercapacitors.