Chitin as a universal and sustainable electrode binder for electrochemical capacitors

We have introduced chitin-bound, activated carbon-based electrode materials dedicated to supercapacitors operated on different electrolyte environments. As a chitin solvent, we have used our original mixture system containing an ionic liquid (1-ethyl-3-methylimidazolium acetate) and a viscosity reducing agent (dimethyl sulfoxide). The prepared electrode material has been tested in terms of morphological, physicochemical, and electrochemical properties. The most attention has been paid to studying the electrochemical performance of composite electrodes in the most common types of liquid electrolytes, i.e. aqueous, organic and ionic liquid electrolytes. A comparative study of the assembled supercapacitors has been made in terms of specific capacitance, charge propagation, cycle stability, and power/energy density. As was demonstrated, the proposed electrode binder material features a very attractive attribute appearing as versatility in terms of employed electrolyte. Regardless of the type of used electrolyte, chitin-bound electrodes display high specific capacitance (128–142 F g−1), good rate capability (up to 92% capacitance retention under 15 A g−1), and excellent cycle stability (75–99% of an initial capacitance). Taking into account the natural origin of chitin and the excellent electrochemical efficiency of tested devices, it appears that synthesized electrode materials represent a promising and green alternative for the development of environmentally benign supercapacitors. [Display omitted] •Universal and sustainable chitin-bound, AC-based electrode material was designed.•IL/DMSO mixture solvent was used in the electrode preparation procedure.•Obtained material exhibited versatility in terms of SC electrolyte compatibility.•It showed high efficiency in aqueous-, organic-, and ionic liquid-based electrolytes.•Tested electrodes exhibited Cs of 128–142 F g−1 and long-term cycle stability of 75–99%.