Sustainable Modification of Chitosan Binder for Capacitive Electrodes Operating in Aqueous Electrolytes

Abstract

Biopolymers emerged in recent years as a promising alternative for a more sustainable manufacturing of electrochemical energy storage systems. In fact, for environmentally friendly aqueous systems, fluorinated polymers are usually adopted. For this reason, substituting these polymers with water processable binders could improve the overall environmental impact of the device. In this study, a low -cost and environmentally friendly modification of chitosan binder for self-standing activated carbon electrodes operating in Na ion, aqueous electrochemical double layer capacitors is reported and discussed.

Impact of Acetate‐Based Hydrogel Electrolyte on Electrical Performance and Stability of Eco‐Friendly Supercapacitors

“…The observed faradaic contribution can be attributed to charge transfer phenomena occurring between functional groups present within chitosan and gelatin, particularly with cationic species such as Na + . In our device, chitosan features hydroxyl (OH) and amine (NH 2 ) functional groups, enhancing the wettability of the carbon electrode surface [11,16] . This enhancement facilitates charge transfer processes and promotes ion adsorption [11,35,36] .…”

“…In our device, chitosan features hydroxyl (OH) and amine (NH 2 ) functional groups, enhancing the wettability of the carbon electrode surface. [11,16] This enhancement facilitates charge transfer processes and promotes ion adsorption. [11,35,36] Additionally, gelatin contains carboxyl (COOH) and amine (NH 2 ) groups that can interact with the activated carbon at the electrode-electrolyte interface.…”

“…[13][14][15] In particular, chitosan, a polysaccharide extracted from crustacean shells, has been employed without negatively affecting SC performance. [16,17] The overall friendliness of SCs is also improved by using water processing for electrolytes. Aqueous electrolytes provide higher ionic conductivity and lower resistance than organic electrolytes.…”

“…Materials like cellulose and its derivatives, alginate, starch, and chitosan, have been successfully applied as binding materials in carbon electrodes for SCs [13–15] . In particular, chitosan, a polysaccharide extracted from crustacean shells, has been employed without negatively affecting SC performance [16,17] . The overall friendliness of SCs is also improved by using water processing for electrolytes.…”