• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.584-587
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• 2011

In this work, the $TiO_2$ and $SnO_2$ thin films as blocking layers were coated directly onto the metal-mesh electrode surface to prevent unnecessary inflow of back-transfer electrons from the electrolyte ($I^-/I_3^-$) to the metal-mesh electrode. The DSCs were fabricated with working electrode of SUS mesh coated with blocking $TiO_2$ and $SnO_2$ layers, dye-attached mesoporous $TiO_2$ film, gel electrolyte and counter electrode of Pt-deposited F:$SnO_2$. From the experimental result, it was ascertained that the efficiency of metal electrode coated with $TiO_2$ by Dip-coating was superior to that of metal electrode coated with $SnO_2$ by Dip-coating and screen printing with the results of experiments. The photo-current conversion efficiency of the cell obtained from optimum fabrication condition was 3% ($V_{oc}$=0.61V, $J_{sc}$=11.64 mA/$cm^2$, ff=0.64) under AM1.5, 100 mW/$cm^2$ illumination.

• Journal of Korean Society on Water Environment
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• v.23 no.3
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• pp.377-384
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• 2007

This study has carried out a performance of dimensionally stable anode for the purpose of decolorization of Rhodamine B (RhB) in water. Seven kinds of 1, 2 and 3 component electrodes were prepared by plating and thermal deposition, which were coated by the oxides of Pt, Ru, Ir, Sn-Sb, Ir-Sn-Sb, Ru-Sn-Sb and Ru-Sn-Ti on Ti metal surface, respectively. Performance for RhB decolorization of the seven electrodes lay in: Ru-Sn-Ti/Ti ${\fallingdotseq}$ Ru-Sn-Sb/Ti > Ir-Sn-Sb/Ti > Sn-Sb/Ti > Ru/Ti > Ir/Ti > Pt/Ti. The effects of electrode area and distance, electrolyte type and concentration, current density and pH were investigated on the decolorization of RhB using Ru-Sn-Ti/Ti electrode. Decolorization of RhB was not influenced by electrode area and distance largely, however wattage was influenced by them. NaCl was superior to the decolorization of RhB than $Na_2SO_4$. Optimum NaCl dosage and current density were 0.5 g/L and $0.183A/cm^2$, respectively. The pH effect of decolorization of RhB was not significant within the range of 3-7.

• Journal of Electrochemical Science and Technology
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• v.12 no.2
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• pp.173-187
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• 2021

In the present research, a simple electrochemical sensor based on a carbon paste electrode (CPE) modified with ZnO-Zn₂SnO₄-SnO₂ and graphene (ZnO-Zn₂SnO₄-SnO₂/Gr/CPE) was developed for the direct, simultaneous and individual electrochemical measurement of Acetaminophen (AC), Caffeine (Caf) and Ascorbic acid (AA). The synthesized nano-materials were investigated using scanning electron microscopy, X-ray Diffraction, Fourier-transform infrared spectroscopy, and electrochemical impedance spectroscopy techniques. Cyclic voltammetry and differential pulse voltammetry were applied for electrochemical investigation ZnO-Zn₂SnO₄-SnO₂/Gr/CPE, and the impact of scan rate and the concentration of H⁺ on the electrode's responses were investigated. The voltammograms showed a linear relationship between the response of the electrode for individual oxidation of AA, AC and, Caf in the range of 0.021-120, 0.018-85.3, and 0.02-97.51 μM with the detection limit of 8.94, 6.66 and 7.09 nM (S/N = 3), respectively. Also, the amperometric technique was applied for the measuring of the target molecules in the range of 0.013-16, 0.008-12 and, 0.01-14 μM for AA, AC and, Caf with the detection limit of 6.28, 3.64 and 3.85 nM, respectively. Besides, the ZnO-Zn₂SnO₄-SnO₂/Gr/CPE shows an excellent selectivity, stability, repeatability, and reproducibility for the determination of AA, AC and, Caf. Finally, the proposed sensor was successfully used to show the amount of AA, AC and, Caf in urine, blood serum samples with recoveries ranging between 95.8% and 104.06%.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.737-744
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• 2016

For electrolysis process using an insoluble electrode, electrochemical performance was greatly affected by the manufacturing method and procedure, such as the firing temperature, pre-treatment, type of precursor solution, coating method, electrode material, etc. Components of the electrode therein is one of the most important factors in electrochemical reaction. To achieve such characteristics, a appropriate ratio of the electrode material should be carefully chosen. The aim of this research was to apply experimental design method in the optimization of electrode component for the maximum generation of oxidants in electrochemical oxidation process. Mixture design, especially expanded simplex lattice design, in DOME (design of mixture experiments) with Design Expert - commercial software - was used to analyze the data. Analysis of variance (ANOVA) showed a high coefficient of determination ($R^2$) value of 0.9470, thus ensuring a satisfactory adjustment of the $3^{rd}$ order special cubic regression model with the experimental data. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the TRO generation concentration and independent variables(mol ratio of 3 electrode components) in a real unit: TRO generation concentration $(mg/L)=TRO\;conc.=98.25{\times}[Ir]+49.71{\times}[Sn]+95.29{\times}[Sb]-16.91{\times}[Ir]{\times}[Sn]-29.47{\times}[Ir]{\times}[Sb]-22.65{\times}[Sn]{\times}[Sb]+703.19{\times}[Ir]{\times}[Sn]{\times}[Sb]$. The optimized formulation of the 3 component electrode for an high TRO (total residual oxidants) generation was acquired at mol ratio of Ir 0.406, Sn 0.210, Sb 0.384 (desirability d value, 1).

• Journal of Environmental Science International
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• v.29 no.10
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• pp.943-949
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• 2020

In this work, we prepared a heterojunction anode with a surface layer of SnO₂-Sb-Ni (SSN) on a Ti/IrO₂ electrode by thermal decomposition to improve the electrochemical activity of the Ti/IrO₂ electrode. The Ti/IrO₂-SSN electrode showed significantly improved electrochemical activity compared with Ti/IrO₂. For the 0.1 M NaCl and 0.1 M Na₂SO₄ electrolytes, the onset potential of the Ti/IrO₂-SSN electrode shifted in the positive direction by 0.1 V_SCE and 0.4 V_SCE, respectively. In 2.0-2.5 V voltages, the concentration in Ti/IrO₂-SSN was 2.59-214.6 mg/L Cl₂, and Ti/IrO₂ was 0.55-49.21 mg/L Cl₂. Moreover, the generation of the reactive chlorine species and degradation of Eosin-Y increased by 3.79-7.60 times and 1.06-2.15 times compared with that of Ti/IrO₂. Among these voltages, the generation of the reactive chlorine species and degradation of Eosin-Y were the most improved at 2.25 V. Accordingly, in the Ti/IrO₂-SSN electrode, it can be assumed that the competitive reaction between chlorine ion oxidation and water oxidation is minimized at an applied voltage of 2.25V.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.537-541
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• 2010

Pt-Sn with various ratios was supported on carbon black after pretreatment in an acidic solution by a reduction method. The Pt/Sn ratio was controlled by varying the concentration of each component in the solution, and the influence of the composition on the electrocatalytic activities was investigated. The crystallinity of the synthesized materials was investigated by XRD (X-ray Diffraction), and the oxidation states of both the platinum and tin were determined by XPS (X-ray Photoelectron Spectroscopy). SEM (Scanning Electron Microscopy)-EDS (Energy Dispersive Spectroscopy) was utilized to examine the morphology and composition of the synthesized electrode, and the particle size of the Pt-Sn was analyzed by TEM (Transmission Electron Microscopy). The electrocatalytic activity for oxygen reduction was evaluated in a 0.5 M $H_2SO_4$ solution using a rotating disk electrode system. The activity and stability were found to be strongly dependent on the electrode composition (Pt/Sn ratio). The catalytic activity and stability for methanol oxidation were also measured using cyclic voltammetry (CV) in a mixture of 0.5 M $H_2SO_4$ and 0.5 M $CH_3OH$ aqueous solution. The addition of proper amount of Sn was found to significantly improve both catalytic activity and stability for methanol oxidation.

• Corrosion Science and Technology
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• v.10 no.2
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• pp.71-75
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• 2011

Corrosion properties of Al-0.3Ga-0.3Sn, Al-0.3Mn-0.3Ga, and Al-0.3Mn-0.3Sn alloys were examined to develop an anode material for Al-air battery with alkaline aqueous or ethanol electrolyte. The results of potentiodynamic polarization tests showed that the electrode potential of the Al alloys were lower than the pure Al, implying the cell voltage can be increased by using one of these alloys for an anode in 4 M KOH aqueous solution. The corrosion rate appeared to be increased by alloying Ga but to be reduced by Sn and Mn in the aqueous solution. The ethanol solution is expected to improve the cell performance in that the electrode potential and the corrosion rate of Al were lower in ethanol solution than in aqueous solution. However the Al-(Ga, Sn, Mn) alloys are not favorable in ethanol solution because of the high potential and corrosion rate.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.449-453
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• 2007

Synthesis of Sn-GIC (Graphite intercalated compound) and its electrochemical characteristics were investigated to find a method for enhancing the performance of carbon anode of lithium ion battery. The content of Sn intercalated in graphite interlayer increased with increase of concentration of $SnCl_2$ solution and increase of the heat treatment temperature of dried graphite after dipped in $SnCl_2$ solution, respectively. And initial discharge capacity increased upon increase of intercalated Sn content. Sn-GIC with excellent electrochemical performance, which can be synthesized by heat treatment at $900^{\circ}C$ after dipped in 1.0 M $SnCl_2$ solution, showed 356 mAh/g of initial discharge capacity and 13% of capacity decay after 10 cycles.

• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.175-182
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• 2008

This study investigates the optimal conditions for electrogenerated hydrogen peroxide production and the application of the electro-Fenton process using DSA electrodes. The influences of parameters for the hydrogen peroxide generation such as electrode materials, electrolyte concentration, current, pH, air flow rate and electrode distance were investigated using a laboratory scale batch reactor. The relative performance for hydrogen peroxide generation of each of the six electrodes is : Ru-Sn-Ti > Ru-Sn-Sb > Ru > Ir > Pt > Sn-Sb. Optimum NaCl dosage, current and air flow rate were 2.0 g/l, 12.5 A and 2 l/min, respectively. When the pH is low, hydrogen peroxide concentration was high. Electrode distance dos not effect to a hydrogen peroxide generation. A complete color removal was obtained for RhB (200 mg/l) at the 8 min mark of the electro-Fenton process under optimum operation conditions of $Fe^{2+}$ 0.105 g/l and 5.0 A. The electro-Fenton process increased initial reaction and decreased final reaction time. However the effect was not high.

• Korean Journal of Materials Research
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• v.16 no.2
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• pp.129-136
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• 2006

In order to get basic information on the reference electrode material for the long life Al concentration sensor in zinc galvanizing melt, the workability and stability of fluorine potential cell with $CaF_2$ single crystal electrolyte were examined carefully at constant temperature for six kinds of reference materials (Zn, Sn, Cd, Bi, Pb, Al-Sn alloy + fluorides). Good workability and stability of the sensor were found in sensor with $Bi+BiF_3$ reference electrode. The Al sensor with $Bi+BiF_3$ reference electrode was assembled and was tested in Zn-Al melt with different Al concentration. The EMF was changed rapidly with the change of Al concentration and was stabilized in a short time. Thus the response of EMF was satisfactory for $CaF_2$ sensor. The correlationship between EMF from the sensor and logarithm of Al concentration has been derived from the least square regression method. E/mV=57.515log[wt% Al]+1883.3 R=0.9717 ($0.013{\leq}[wt% Al]{\leq}0.984$) The EMF from Al sensor was increased linearly against logarithm of [wt% Al]. The fluorine potential of Zn-Al melt was also calculated to be in the range of $10^{-60}{\sim}10^{-61}$ Pa for the present experiemental condition.