Abstract
Aromatic and aliphatic N-heterocyclic chemical salts were synthesized by counter-anion-exchange reactions after substitution reactions in order to apply them as organic electrolyte supporters in an electrochemical capacitor (super capacitor). The aromatic N-heterocyclic salts were N-methylpyridinium tetrafluoroborate ([MPy]+[BF4]−), N-methylpyridinium hexafluorophosphate ([MPy]+[PF6]−), 1,3-dibuthylimidazolium tetrafluoroborate ([DI]+[BF4]−), 1,3-dibuthylimidazolium hexafluorophosphate ([DI]+[PF6]−), 1-buthyl-4-methyl-1,2,4-triazolium tetrafluoroborate ([BMTA]+[BF4]−), and 1-buthyl-4-methyl-1,2,4-triazolium hexafluorophosphate ([BMTA]+[PF6]−). The aliphatic N-heterocyclic salts were N,N-dimethylpiperilidium tetrafluoroborate ([DMP]+[BF4]−), N,N-dimethylpiperilidium hexafluorophosphate ([DMPy]+[PF6]−), N,N-dimethylpyrrolidium tetrafluoroborate ([DMPy]+[BF4]−) and N,N-dimethylpyrrolidium hexafluorophosphate ([DMPy]+[PF6]−), 1-ethyltriethamine tetrafluoroborate ([E-TEDA]+[BF4]−), and 1-ethyltriethamine hexafluorophosphate ([E-TEDA]+[PF6]−), respectively. We confirmed the successful synthesis of the aromatic and aliphatic N-heterocyclic chemical salts by 1H-NMR, FT-IR, and GC/MS analysis before conducting the counter-anion-exchange reactions. Then, we determined the electrochemical potential of vanadium acetylacetonate (V(acac)3) under acetonitrile in the presence of the N-heterocyclic chemical salts as energy-storage chemicals. By cyclic voltammetry, the maximum voltages with the N-heterocyclic chemical salts in acetonitrile reached 2.2 V under a fixed current value. Charge-discharge experiments were performed in the electrochemical capacitor with an anion-exchange membrane using a non-aqueous electrolyte prepared with a synthesized N-heterocyclic salt in acetonitrile.
Highlights
IntroductionElectrochemical capacitors (supercapacitors) are good energy-storage systems. A typical electrochemical capacitor consists of two electrodes, an ion-permeable membrane, and an electrolyte packaged in a sealed container [1,2]
Used electrolytes are aqueous solutions such as sulfuric acid (H2 SO4 ) [7], potassium hydroxide (KOH) [8], organic electrolytes based on propylene carbonate and acetonitrile [9,10,11], and ionic liquids consisting of cations, such as imidazolium, pyridinium, and quaternary ammonium, and anions, such as halogen, tetrafluoroborate, and hexafluorophosphate [12,13]
The Cyclicvoltammograms voltammograms (CVs) results for V(acac)3 were found to be stable from −2.5 to 1.0 V when using electrolytes as aromatic N-heterocyclic chemical salts with acetonitrile
Summary
Electrochemical capacitors (supercapacitors) are good energy-storage systems. A typical electrochemical capacitor consists of two electrodes, an ion-permeable membrane, and an electrolyte packaged in a sealed container [1,2]. Used electrolytes are aqueous solutions such as sulfuric acid (H2 SO4 ) [7], potassium hydroxide (KOH) [8], organic electrolytes based on propylene carbonate and acetonitrile [9,10,11], and ionic liquids consisting of cations, such as imidazolium, pyridinium, and quaternary ammonium, and anions, such as halogen, tetrafluoroborate, and hexafluorophosphate [12,13]. Most of these aqueous electrochemical capacitor systems cause undesirable ion cross-over because of the membrane’s permeability, which leads to power and energy loss. Despite the advantages of a non-aqueous electrolyte solution in the electrochemical capacitor, there have been few studies of this setup because of the difficulties in synthesizing the organic electrolyte, the low solubility of vanadium salts as energy-storage materials, and the physical problem of the membrane for ion exchange during the charge-discharge process under a non-aqueous electrochemical capacitor
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
