• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1393-1395
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• 2003

• Journal of the Korean Electrochemical Society
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• v.13 no.3
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• pp.211-216
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• 2010

Boron trifluoride lithium methacrylate ($BF_3$LiMA)-based gel polymer electrolytes (GPEs) were synthesized with various $BF_3$LiMA concentration to elucidate the effect on ionic conductivity and electrochemical stability by a AC impedance and linear sweep voltammetry (LSV). As a result, the highest ionic conductivity reached $5.3{\times}10^{-4}Scm^{-1}$ at $25^{\circ}C$ was obtained for 4 wt% of $BF_3$LiMA. Furthermore, high electrochemical stability up to 4.3 V of the $BF_3$LiMA-based GPE was observed in LSV measurement since the counter anion was immobilized in this self-doped system. On the other hand, it was assumed that there was a rapid decomposition of electrolytes on a lithium metal electrode which results in a high solid electrolyte interface (SEI) resistance. However, a high stability toward graphite or lithium cobalt oxide (LCO) electrode thereby a low SEI resistance was observed from the AC impedance measurement as a function of storage time at $25^{\circ}C$. Consequently, the high ionic conductivity, good electrochemical stability and the good interfacial compatibility with graphite and LCO were achieved in $BF_3$LiMA-based GPE.

• Membrane Journal
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• v.28 no.4
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• pp.260-264
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• 2018

Poly (ethylene oxide) (PEO)/Ag nanoparticles (AgNPs)(precursor : $AgBF_4$)/p-benzoquinone (p-BQ) composite membrane was prepared for olefin/paraffin separation. As a result, the performance of composite membrane was observed to be maintained at selectivity of 10 and permeance of 15 GPU up to 100 hours. The performance of the membrane was maintained for 100 hours was attributable to that Ag ions could be converted into stable Ag NPs by addition of p-BQ. Furthermore, the surface was partially polarized by the electron acceptor p-BQ, resulting in the formation of olefin carrier. In this study, since the cost of $AgBF_4$ used as a precursor of Ag NPs was relatively higher, $AgNO_3$ was utilized. As a result, it was confirmed that $AgNO_3$ couldn't show the stable formation of nanoparticle, resulting in the poor separation performance.

• Journal of the Korean Chemical Society
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• v.32 no.5
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• pp.452-457
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• 1988

Capacity factors (k') of some inorganic anions including $BF_4^{-1}$ were measured on cetylpyridinium coated column, and with dynamic system using tetrabutylammonium salicylate on PRP-1 reversed-phase column, respectively. After optimum separation condition was obtained this method was applied to the determination of boron in some different type samples.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.4
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• pp.257-262
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• 2013

The fluorine-containing waste water tends to show a higher removal efficiency through the coagulative precipitation process with calcium. However the tetrafluoroborate produced from the etching process is difficult to remaval due to it's low reactivity with calcium. The objective of this study is improving the efficiency of fluoride ion removal in tetrafluoroborate through decomposing. Research on tetrafluoroborate decomposition depending on reaction pH, temperature, and aluminum dosage were conducted, using a laboratory-scale reactor. The result shows that the reaction of tetrafluoroborate with aluminum is faster with lower pH, higher water temperature, and higher Al/T-F (Aluminum/Total Fluoride) mole ratio. It is found that there was no big change in concentration after over 120 minutes of reaction. This study is to be able to improve the efficiency of tetrafluoroborate and fluoride wastewater treatment by using aluminum.

• Journal of Electrochemical Science and Technology
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• v.10 no.1
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• pp.55-60
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• 2019

Herein, the effect of counter anions on the formation of a solid electrolyte interphase (SEI) in a propylene carbonate (PC)-based electrolyte solution was investigated. Although the reversible capacities were different, reversible intercalation and de-intercalation of lithium ions occurred in the graphite negative electrode in the PC-based electrolyte solutions containing 1 M $LiClO_4$, $LiPF_6$, $LiBF_4$, and $LiCF_3SO_3$ at low temperature ($-15^{\circ}C$). This indicated that the surface films acted as an effective SEI to suppress further co-intercalation and decomposition reactions at low temperature. However, the SEIs formed at the low temperature were unstable in 1 M $LiPF_6$ and $LiBF_4/PC$ at room temperature ($25^{\circ}C$). On the other hand, increasing reversible capacity was confirmed in the case of $LiCF_3SO_3/PC$ at room temperature, because the SEI formed at the low temperature was still maintained. These results suggest that counter anions are an important factor to consider for the formation of effective SEIs in PC-based electrolyte solutions.

• Korean Membrane Journal
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• v.8 no.1
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• pp.43-49
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• 2006

Complex membranes consisting of silver salt ($AgBF_4,\;AgCF_3SO_3,\;AgSbF_6,\;AgNO_3$) and poly(vinyl alcohol) (PVA) or crosslinked PVA (CPVA) were prepared and tested for the separation of propylene/propane mixtures. For the tested membranes, the complex membranes containing $AgBF_4$ exhibited the highest separation properties, i.e., approximately 20 GPU ($1 GPU=10^{-6}cm^3 (STP)/(cm^2 sec cmHg)$) and 100 of selectivity at 0.2 of silver mole fraction. The CPVA membranes containing silver salt always showed higher selectivity than PVA membranes, presenting silver ions coordinated to -CHO are more effective than those to -OH groups. The threshold silver concentration of CPVA membranes was lower than that of PVA membranes, which might be due to stronger interaction of silver ions with -CHO than that with -OH. The composition at which the selectivity is the highest did not significantly depend on the crosslinking, but did on the kind of silver salt.

• Membrane Journal
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• v.31 no.1
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• pp.61-66
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• 2021

This study was a study on an facilitated transport membrane to replace the cryogenic separation method currently used in olefin/paraffin separation. Cost reduction is also a very important factor to commercialize facilitated transport membranes. However, AgBF4, which has been studied a lot, is a relatively expensive silver salt. To replace this, a PEBAX-2533/ AgCF3SO3/Al(NO3)3 composite film was prepared using relatively inexpensive AgCF3SO3. It was analyzed through SEM, FT-IR, and RAMAN. Through this study, it was confirmed that the polymer matrix affects the long-term stability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.295-298
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• 1998

We have investigated ionic conductivity and electrochemical stability of the electrolytes containing organic solvent. Ion conductivities were measured between 10 and 80$^{\circ}C$, and electrochemical stabilities were determined by cyclic voltammetry on glassy carbon, platinum and aluminum electrodes. Ionic conductivity of electrolyte(EC:DEC=1:1) with IM LiPF$\_$6/ shows better than that of the other electrolytes having Li salts. The IM LiBF$_4$-PC electrolyte exhibits good electrochemical stability. IM LiPF$\_$6/ (EC:DEC=1:1) and IM LiPF$\_$6/ (EC:DMC=1:1) electrolytes are used for the high capacity of battery system.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.326-332
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• 1982

The structure of the complex extracted from an aqueous solution containing methylene blue and tetrafluoroborate with 1,2-dichloroethane has been investigated by comparing IR spectrum of the extract with those of pure components and appeared to be an 1 : 1 contact ion-pair between monovalent ions of opposite charge. The extraction constant obtained from the absorbance data measured at 658nm in 1,2-dichlorethane has a value of 1.1${\times}$at$10^4M{-1}$ 25$^{\circ}$C in the range from 1.43${\times}10^{-2}$ to 2.86${\times}10^{-1}$M HF. In the solvent extraction with nitrobenzene, the identical experiments show that extraction constants are increased with HF concentration possibly due to dissociation of the ion-pair in nitrobenzene.