Sustainable and Printable Nanocellulose-Based Ionogels as Gel Polymer Electrolytes for Supercapacitors

Abstract

A new gel polymer electrolyte (GPE) based supercapacitor with an ionic conductivity up to 0.32–0.94 mS cm−2 has been synthesized from a mixture of an ionic liquid (IL) with nanocellulose (NC). The new NC-ionogel was prepared by combining the IL 1-ethyl-3-methylimidazolium dimethyl phosphate (EMIMP) with carboxymethylated cellulose nanofibers (CNFc) at different ratios (CNFc ratio from 1 to 4). The addition of CNFc improved the ionogel properties to become easily printable onto the electrode surface. The new GPE based supercapacitor cell showed good electrochemical performance with specific capacitance of 160 F g−1 and an equivalent series resistance (ESR) of 10.2 Ω cm−2 at a current density of 1 mA cm−2. The accessibility to the full capacitance of the device is demonstrated after the addition of CNFc in EMIMP compared to the pristine EMIMP (99 F g−1 and 14.7 Ω cm−2).

Investigating the Correlation between Electrolyte Concentration and Electrochemical Properties of Ionogels

“…It was claimed that this results from the aggregation of ionic liquid. Meanwhile, the distorted CV plots could be due to the increasing internal resistance [ 47 ], Fontaine and Janani suggest that the deformed CV plots imply the resistive behavior of ionogel, behaving more like a resistor than a supercapacitor [ 48 , 49 ]. Moreover, the electrolyte–electrode charge transfer would also result in deviation from rectangular shape, while the reactions are considered pseudocapacitive provided that the charge transfer is reversible [ 50 ].…”

Multifunctional Nanomaterials for Energy Applications

“…González-Gil et al [19] prepared a new nanocellulose-based gel polymer electrolyte (GPE) to be used in supercapacitors. The authors synthesized the GPE from a mixture of an ionic liquid (1-ethyl-3-methylimidazolium dimethyl phosphate) with carboxymethylated cellulose nanofibers at different weight ratios.…”