Cellulose nanocrystals in biodegradable electronics
Ionic driven devices have been increasingly investigated in the drive to develop flexible and bio-integrable electronics. One such device is a polyelectrolyte gel diode capable of rectifying ionic current. Herein, bioderived cellulose nanocrystals (CNCs) are used to create light, flexible, biocompatible, and biodegradable ionic diode devices. We demonstrated rectification behavior from a fixed junction between two agarose hydrogels doped with cationic and anionic cellulose nanocrystals. The current rectification ratio reaches 70 reproducibly and the currentâˆ’voltage characteristics of the CNCâˆ’hydrogel diode are influenced by concentration, gel thickness, scanning frequency, and applied voltage. In addition, we explore the mechanism behind the rectification of ionic current based on a theoretical electrochemical model and validate it using experimental data. We show that the diode operates via a physical mechanism that involves the electrochemical generation of proton and hydroxyl ions at the electrodes to generate current.
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