Green and cost-effective synthesis of flexible, highly conductive cellulose nanofiber/reduced graphene oxide composite film with deep eutectic solvent

Developing efficient strategy for nanomaterials dispersion is the key for promoting the utilization of cellulosebased composite in energy storage devices. In this study, an instant synthesis method for cellulose nanofiber (CNF)/reduced graphene oxide (rGO) composite film with a deep eutectic solvent (DES) based on choline chloride and urea as a media is developed. This DES shows favorable abilities of recyclability, materials dispersion, and could adjust the pH value for reaction systems of neutral to alkaline which in favor of electrostatic repulsion arising from deprotonated carboxyl groups at the composite surface. As-obtained films feature excellent flexibility, high electrical conductivity (as high as 26.47 S.cm(-1)) and well electrochemical properties. Furthermore, a little amount of nitrogen atoms (similar to 3.0 at%) could be introduced in the composite at a mild condition. Overall, this approach offers the potential for cost-effective, environmentally friendly and large-scale production of cellulose-based electrode and numerous advanced applications.

Automated summary

Developing an instant synthesis method using a deep eutectic solvent, this study successfully produced cellulose nanofiber/reduced graphene oxide composite films with excellent flexibility and high electrical conductivity, showing potential for large-scale production of cellulose-based electrodes.