Trialkyl-Substituted Imidazolium-Based Ionic Liquids for Electrochemical Applications: Basic Physicochemical Properties

Abstract

The trialkyl-substituted imidazolium-based ionic liquids (ILs) are considered to be promising as supporting electrolytes for electroplating and other electrochemical applications because of their increased stability compared to that of dialkyl-substituted compounds. Basic properties like density, viscosity, and conductivity of 1-butyl-2,3-dimethylimidazolium tetrafluoroborate (BMMImBF 4 ), 1-butyl-2,3-dimethylimidazolium azide (BMMImN 3 ), and their mixtures were measured. The thermal stability of the azide IL permits its use up to 423.15 K, whereas the upper temperature limit for telrafluoroborate IL extends to 623.15 K. The electrochemical stability with regard to cathodic reduction was the same for both ILs; the decomposition potential was about -1.9 V versus the Ag/AgCl reference electrode. However, the resistance to electrochemical oxidation at the anode was much lower for the azide IL. The decomposition potential was 0.5 V against 2.05 V for the tetrafluoroborate IL.

Ionic liquid-based polymer gel electrolytes for symmetrical solid-state electrical double layer capacitor operated at different operating voltages

“…5(a). The current flow through the sample was almost constant until the applied voltage swept to further positive value and reached a voltage breakdown at +2.4 V. The voltage breakdown can be due to the occurrence of anions oxidation in the 7.5 wt.% of [bdmim]BF 4 of GPE-IL sample in which fluorocarbon has formed [52][53]. This also implies the cathodic limit of the tetrafluoroborate salt due to the reduction of the imidazolium-based cation.…”

Ionic Liquids in Microemulsions—A Concept To Extend the Conventional Thermal Stability Range of Microemulsions

“…11 Other studies concern the use of ionic liquids as electrolytes in batteries, 12 double layer capacitors or solar cells. 13,14211,212,213,214,215,216,217,218 In recent years, progress has been made in the determination of thermodynamic and transport properties of RTILs, with imidazolium-based compounds being in the focus of many studies.…”

Influence of Temperature on Supercapacitor Components

“…All-solid-state supercapacitors using polymer gel electrolytes do not need additional commercial separators since the polymer membrane itself serves the purpose of both electrolyte and separator [71,201,202]. A natural and flexible eggshell membrane is proposed for a supercapacitor separator with enhanced thermal stability and mechanical strength [203].…”