• 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.

• Journal of the Korean Ceramic Society
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• v.37 no.3
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• pp.233-239
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• 2000

Sr0.9Bi2+xTa2O9(x=0, 0.1, 0.2, 0.3) thin films on IrO2/SiO2/Si or Pt/Ti/SiO2/Si substrate were prepared by spin coating method using SBT stock solutions synthesized by MOD process. SBT thin films on IrO2 transformed to layered perovskite phase at $700^{\circ}C$, but showed low breakdown voltage due to their porous microstructure. The smaple of Sr0.9Bi2+xTa2O9 composition showed the best dielectric and electrical properties. When the sample of the same composition was annealed at 80$0^{\circ}C$, the dielectric and electric properties were improved due to the grian growth and dense surface. the remanent polarization values(2Pr) at $\pm$3 V for IrO2 and Pt electrodes were 10.5, 7.15$\mu$C/$\textrm{cm}^2$, respectively. The SBT thin film with IrO2 electrode showed the lower coercive field. The leakage current density and breakdown voltage of SBT thin films on IrO2 were higher than those on Pt.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.1
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• pp.14-19
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• 2003

The effect of the Pt electrode and the $Pt-IrO_2$ hybrid electrode on the performance of ferroelectric device was investigated. The modified Pt thin films with non-columnar structure significantly reduced the oxidation of TiN diffusion barrier layer, which rendered it possible to incorporate the simple stacked structure of Pt/TiN/poly-Si plug. When a $Pt-IrO_2$ hybrid electrode is applied, PZT thin film properties are influenced by the thickness and the partial coverage of the electrode layers. The optimized $Pt-IrO_2$ hybrid electrode significantly enhanced the fatigue properties of the PZT thin film with minimal leakage current.

• Journal of the Korean Applied Science and Technology
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• v.31 no.2
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• pp.190-196
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• 2014

The sol-gel method was used to prepare binary metal oxide ($IrO_2-RuO_2$) pH sensor. The electrodes that mole percent compositions (mol%) of $IrO_2$ and RuO2 were 70:30 and 30:70 were selected. The characterizations of Nernstian response over pH range, response rate, interference on alkaline metals and reproducibility were investigated. Also the electroanalytical properties of these electrodes were evaluated in comparison with a commercial glass pH electrode. The composition of $IrO_2:RuO_2$ 70:30 mol% was chosen as better electrode formulation. The electrode was not susceptible to the action of interfering ions such as $Li^+$, $Na^+$ and $K^+$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.8
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• pp.694-699
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• 2000

S $r_{0.9}$/B $i_{2.1}$/T $a_{2}$/ $O_{9}$ solutions was synthesized by MOD (metalorganic decomposition) method. SBT thin films with 2000$\AA$ thickness were prepared on Ir $O_2$/ $SiO_2$/Si and Pt/Ti/ $SiO_2$/Si substrates using the spin coating process and then investigated the dielectric and electrical properties of them. In the case of using Ir $O_2$bottom electrode the hysteresis loop was saturated at lower temperature than Pt/Ti electrode but the breakdown phenomenon was occurred at low voltage because of the rough surface morphology and porous microstructure of SBT thin films. As the results of the fatigue and imprint characteristics related to the lifetime and reliability of devices after 10$^{10}$ cycles the fatigue rates were about 10% at the Ir $O_2$and Pt/Ti bottom electrodes. Both SBT thin films with Ir $O_2$ and with Pt/Ti bottom electrodes show a slight tendency to imprint after 10$^{9}$ cycles but do not lead to a failure.e.e.

• Environmental Engineering Research
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• v.25 no.3
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• pp.324-334
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• 2020

Tannery wastewater is known to contain high concentrations of organic compounds, pathogens, and other toxic inorganic elements such as heavy metals, nitrogen, sulfur, etc. Biological methods such as aerobic and anaerobic processes are unsuitable for tannery wastewater treatment due to its high salinity, and electrochemical oxidation offers a promising method to solve this problem. In this study, raw tannery wastewater treatment using DSA® Ti/RuO₂, Ti/IrO₂ and Ti/BDD electrodes with continuous flow systems was examined. Effects of current densities and electrolysis times were investigated, to evaluate the process performance and energy consumption. The results showed that a Ti/BDD electrode is able to reach higher treatment efficiency than Ti/IrO₂, and Ti/RuO₂ electrodes across all parameters, excluding Total Nitrogen. The main mechanism of tannery wastewater oxidation at a Ti/BDD electrode is based on direct oxidation on the electrode surface combined with the generation of oxidants such as °OH and Cl₂, while at DSA® Ti/RuO₂ and Ti/IrO₂ electrodes, the oxidation mechanisms are based on the generation of chlorine. After treatment, the effluents can be discharged to the environment after 6-12 h of electrolysis. Electrooxidation thus offers a promising method for removing the nutrients and non-biodegradable organic compounds in tannery wastewater.

• Journal of Surface Science and Engineering
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• v.40 no.5
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• pp.203-208
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• 2007

Preliminary studies were conducted to develop a dimensionally stable anode (DSA)electrode prepared by reactive sputtering method. The microstructure, surface morphology and electrochemical properties of iridium oxide $(IrO_2)$ coatings synthesized by unbalanced magnetron sputtering (UBMS) and conventional DSA electrode were compared. In addition, the possibilities of $IrO_2$ films synthesized by UMB on a real DSA electrode were investigated by electro-chemical application test. The degree of non-stoichiometry and surface area were closely related to the electro-chemical activity of the $IrO_2$ electrode. The feasibility of making a DSA electrode prepared by PVD technique was demonstrated through the present work.

• Journal of the Korean Ceramic Society
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• v.38 no.1
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• pp.39-44
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• 2001

솔-젤법으로 S $r_{0.9}$B $i_{2.1}$T $a_2$$O_{9}$ stock solution을 합성하고, Ir $O_2$/ $SiO_2$/Si 및 기판 위에 스핀코팅법으로 약 2000$\AA$ 정도의 두께를 가지고 SBT 박막을 제조하였다. Pt/Ti $O_{x}$ 전극을 사용한 SBT 박막과 비교하였을 때 Ir $O_2$전극을 사용한 SBT 박막의 경우 더 낮은 급속 열처리 온도 즉, 72$0^{\circ}C$에서 형석상에서 층상 페롭스카이트 상으로의 상전이가 관찰되었다. 그리고, Ir $O_2$전극을 사용한 SBT 박막은 낮은 열처리에서 결정성장이 이루어졌다. Ir $O_2$전극을 사용한 SBT 박막은 $650^{\circ}C$에서 열처리하였을 때 포화된 이력곡선을 얻었지만, Pt/Ti $O_{x}$ 전극을 사용한 SBT 박막은 $700^{\circ}C$에서 열처리하였을 때 이력곡선이 관찰되었다. Ir $O_2$전극을 사용한 SBT 박막은 $700^{\circ}C$의 열처리에서 8.79 $\mu$C/$ extrm{cm}^2$ (3V)의 2Pr 값을 나타내었다.나타내었다.다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.177-184
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• 1996

We adopted the $Pt/SiO_{2}/Si$ and the $Ir/SiO_{2}/Si$ substrates of which buffer layer is $PbTiO_{3}$ to improve electrode and interfacial properties of PZT thin film deposited by reactive sputtering method using metal target in this study. We got PZT thin film to have highly oriented(100) structure and good crystallinity using buffer layer in Pt bottom-electrode, though randomly oriented PZT thin film was obtained without buffer layer. Although great improvement of PZT phase formation on Ir bottom-electrode with buffer layer was not observed, we observed the increase of remennant polarization and the decrease of coercive field compared with properties of PZT thin films on the Pt bottom-electrode. So we got the results of the increase of dielectric constant using buffer layer on fabrication of PZT thin film and the better dielectric properties in PZT thin film using Ir bottom-electrode compared with that using Pt bottom-electrode.

• Journal of the Korean Ceramic Society
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• v.39 no.4
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• pp.341-345
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• 2002

The effect of the Pt electrode and the $Pt-IrO_2$ hybrid electrode on the performance of ferroelectric device was investigated. The modified Pt thin films with non-columnar structure significantly reduced the oxidation of TiN diffusion barrier layer, which rendered it possible to incorporate the simple stacked structure of Pt/TiN/poly-Si plug. When a $Pt-IrO_2$ hybrid electrode is applied, PZT thin film properties are influenced by the thickness and the partial coverage of the electrode layers. The optimized $Pt-IrO_2$ hybrid electrode significantly enhanced the fatigue properties with minimal leakage current.