Cationic cellulose Nanofibrils-based electro-actuators: The effects of counteranion and electrolyte

Abstract

Cellulose-based electro-actuators have enormous potential in various applications, e.g. artificial muscles, soft grippers, medical devices, just to name a few, owing to their high mechanical strength, lightness and natural abundance. However, significant challenges remain in the fabrication of such electro-actuators featuring low operating voltage and fast response kinetics. We report here a facile fabrication route towards high-performance electro-actuators composed of CNFs films doped with ionic liquids or lithium salts and sandwiched by two thin film gold electrodes. Large bending motion at voltages as low as 3.0 V could be observed. The size effect of both anions and cations on the actuation was comprehensively investigated. CNF-TFSI@LiTFSI and CNF-BF4@EMIM-BF4 electro-actuators presented the best bending strain under an AC voltage of 3.0 V. This work provides new inspiration in the design of natural polymer-based high-performance electro-actuators.

Keywords

• Electro-actuators
• Cellulose nanofibrils
• Ionic liquids
• Soft robotics
• Anion influence