Conducting and interface characterization of carbonate-type organic electrolytes containing EMImBF₄as an additive against activated carbon electrode

Abstract

Carbonate-type organic electrolytes were prepared using propylene carbonate (PC) and dimethyl carbonate (DMC) as a solvent, quaternary ammonium salts, and by adding different contents of 1-ethyl-3-methyl imidazolium tetrafluoroborate (EMImBF 4 ). Cyclic voltammetry and linear sweep voltammetry were performed to analyze conducting behaviors. The surface characterizations were analyzed by scanning electron microscopy method and X-ray photoelectron spectroscopy. From the experimental results, increasing the EMImBF 4 content increased the ionic conductivity and reduced bulk resistance and interfacial resistance. In particular, after adding 15 vol% EMImBF 4 in 0.2 M SBPBF 4 PC/DMC electrolyte, the organic electrolyte showed superior capacitance and interfacial resistance. However, when EMImBF 4 content exceeded 15 vol%, the capacitance was saturated and the voltage range decreased.

KOH-activated graphite nanofibers as CO2adsorbents

“…Such materials include activated carbon, activated carbon fibers, carbon nanofibers, graphite nanofibers (GNFs), mesoporous carbons, and graphite [16][17][18][19][20][21][22]. Among these, activated carbons and activated carbon fibers have been widely used in the field of CO 2 adsorption.…”

“…Their results exhibited the best CO 2 adsorption capacity so far (59.2 mg/g). These GNFs exhibited a narrow pore-size distribution with a uniform distribution of pores on the fiber surface, which are particularly good characteristics for the frequent adsorption and desorption of carbon dioxide [18][19][20][21][22][23][24][25]. In all these cases, it is the total microporosity of the materials that is a critical factor in determining their adsorption capability, and chemical activation with KOH is a significant means to produce such microporosity.…”

Ion conducting properties of imidazolium salts with tri-alkyl chains in organic electrolytes against activated carbon electrodes

“…The capacitances increased to 133.7 F·g -1 with addition of BMMImBF 4 ILs additives at 10%. It is speculated that ions were effectively adsorbed and desorbed between the electrolyte and the surface or pores of the electrode.…”

“…Different volume ratios (5, 10, 15, and 20 vol%) of BMMImBF 4 were added to the prepared electrolyte, which was then stirred for 12 h. The chemical structures of BMImBF 4 and BMMImBF 4 are shown in Fig. 1.…”

“…The electrode is prepared using carbon materials such as activated carbon, graphene, or graphite fibers [4][5][6][7]. Among the carbon materials, activated carbon, which has a high specific surface area and a large number of pores, is suitable for the capacitor electrode.…”