• Journal of the Korean Electrochemical Society
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• v.13 no.2
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• pp.123-127
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• 2010

An assembled-graphite/DSA(Dimensionally Stable Anode) was prepared using graphite powder to increase durability and energy efficiency of redox flow battery and investigated its electrochemical properties in vanadium-based electrolyte. The cyclic voltammetry (CV) was carried out in the voltage range of -0.7V and 1.6V vs. SCE at 5 mV/sec scan rate to analyze vanadium redox reaction. From the CV results, the assembled-graphite/DSA electrode showed a fast couple reaction and good reversibility in 2M $VOSO_4$ + 2.5 M $H_2SO_4$ electrolyte. Therefore, it has been expected that this electrode increases power density as well as energy density of redox flow battery.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.769-769
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• 2005

• 한국전기화학회:학술대회논문집
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• 2002.11a
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• pp.77-117
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• 2002

• Journal of Electrochemical Science and Technology
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• v.9 no.1
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• pp.20-27
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• 2018

We describe a redox-enhanced electric double-layer capacitor (EDLC) that turns the electrolyte in a conventional EDLC into an integral, active component for charge storage-charge is stored both through faradaic reactions with soluble redox-active molecules in the electrolyte, and through the double-layer capacitance in a porous carbon electrode. The mixed-redox electrolyte, composed of vanadium and iodides, was employed to achieve high power density. The electrochemical reaction in a supercapacitor with vanadium and iodide was studied to estimate the charge capacity and energy density of the redox supercapacitor. A redox supercapacitor with a mixed electrolyte composed of 0.75 M NaI and 0.5 M $VOSO_4$ was fabricated and studied. When charged to a potential of 1 V, faradaic charging processes were observed, in addition to the capacitive processes that increased the energy storage capabilities of the supercapacitor. The redox supercapacitor achieved a specific capacity of 13.44 mAh/g and an energy density of 3.81 Wh/kg in a simple Swagelok cell. A control EDLC with 1 M $H_2SO_4$ yielded 7.43 mAh/g and 2.85 Wh/kg. However, the relatively fast self-discharge in the redox-EDLC may be due to the shuttling of the redox couple between the polarized carbon electrodes.

• Journal of the Korean Ceramic Society
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• v.44 no.1 s.296
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• pp.1-5
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• 2007

Fining and homogenization of melts during batch melting is closely related to the redox reaction of polyvalent element M (M: Sb, As etc), $M^{(x+n)+}+n/2O^{2-}{\rightarrow}M^{x+}+n/4O_2$. In this study, square wave voltammetry (SWV) measurements were performed to examine the redox behavior of an antimony ion in cathode ray tube (CRT) glass melts. According to results, well-separated two peaks are shown at low temperature while only one peak is shown at high temperature in voltammograms, which reveals that redox reaction of antimony consist of two steps: $Sb^{5+}/Sb^{3+}\;and\;Sb^{3+}/Sb^0$, depending on the temperature. Based on the peak potential shown in the voltammogram, the thermodynamic data and the redox ratio for two redox couple were determined.

• Journal of the Korean Electrochemical Society
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• v.16 no.3
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• pp.145-150
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• 2013

In this study, the electrochemical investigation of various electrodes for reverse electrodialysis using potassium ferrocyanide and potassium ferricyanide as a redox system was carried out. Cyclic voltammetry was the employed method for this electrochemical study. From the results of cyclic voltammograms for various electrode materials, i.e., Au, Vulcan supported Pt, activated carbon, carbon nanofiber, Vulcan, the Vulcan electrode showed the lowest overpotential, but the Pt electrode having slightly higher overpotential obtained slightly higher anodic and cathodic current densities for the $Fe(CN)_6{^{4-}}/Fe(CN)_6{^{3-}}$ redox couple. The cyclic voltammograms for the Vulcan electrode confirmed very good electrochemical reversibility and kinetic behavior. As a result, among the electrode materials, the Vulcan electrode is the most promising electrode material for reverse electrodialysis.

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1433-1439
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• 2014

We report on the influence of water as an electrolyte on the photovoltaic performances. The photovoltaic performance was shown to be quite sensitive to the substituent on the donor group. An optimized efficiency of 4.41% in the presence of 100% water content using $I^-/I{_3}^-$ redox couple was obtained using the D21L6 organic dye.

• 한국전기화학회:학술대회논문집
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• 1998.10a
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• pp.39-39
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• 1998

• Current Photovoltaic Research
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• v.2 no.1
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• pp.18-27
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• 2014

Dye-sensitized solar cells (DSSCs), developed two decades ago, are considered to be an attractive technology among various photovoltaic devices because of their low cost, accessible dye chemistry, ease of fabrication, high power conversion efficiency, and environmentally friendly nature. A typical DSSCs consists of a dye-coated $TiO_2$ photoanode, a redox electrolyte, and a platinum (Pt)-coated fluorine-doped tin oxide (FTO) counter electrode. Among them, redox electrolytes have proven to be extremely important in improving the performance of DSSCs. Due to many drawbacks of iodide electrolytes, many research groups have paid more attention to seeking other alternative electrolyte systems. With regard to this, one-electron outer sphere redox shuttles based on cobalt complexes have shown promising results: In 2014, porphyrin dye (SM315) with the cobalt (II/III) redox couple exhibited a power conversion efficiency of 13% in DSSCs. In this review, we will provide an overview and perspectives of cobalt redox electrolytes in DSSCs.

• ETRI Journal
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• v.26 no.6
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• pp.647-652
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• 2004

A new ionic liquid, 1-vinyl-3-heptylimidazolium iodide (VHpII), was synthesized and applied as a redox electrolyte for dye-sensitized solar cells. The chemical structure of the synthesized VHpII was confirmed using $^1H$ NMR. Thermogravimetric analysis showed that the VHpII was stable for thermal stress of up to $250^{\circ}C$. The energy conversion efficiencies of the VHpII-based dye-sensitized solar cells were investigated in terms of the effect of a lithium iodide addition. A solar cell containing the redox couple of VHpII and iodine showed a conversion efficiency of 2.63% under 1 sun light intensity at AM 1.5. Adding 0.4 M LiI results in a conversion efficiency of 3.63%, which was an improvement of about 40%. The increased conversion efficiency was ascribed to an increase in external quantum efficiency.