• Journal of the Korean Vacuum Society
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• v.5 no.1
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• pp.67-72
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• 1996

$RU_{1-x}Ir_xO_2$ films were deposited on the quartz substrate by a spray pyrolysis method. The x-ray diffraction patterns showed that the structure of the $RU_{1-x}Ir_xO_2$ film was tetragonal and the lattice constant $a_o$ and $c_o$ were increased from 4.495 A to 4.058 A and from 3.092A to 3.156 A, respectively as the Ir composition varied from 0.0 to 1.0. The $RU_{1-x}Ir_xO_2$ film was metallic and the resistivity of the samples was increased from $7{\times}10^{-5}{\Omega}\textrm{cm}$ to $48{\times}10^{-5}{\Omega}\textrm{cm}$ with increasing the Ir x. The surface of the sample was slightly roughed, the grain size and the grain boundary width were increased as the Ir composition varied from 0.0 to 1.0.

• Korean Journal of Materials Research
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• v.13 no.2
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• pp.69-73
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• 2003

In this work, $IrO_2$thin films as bottom electrode of ferroelectric capacitors were deposited and characterized. The $IrO_2$films deposited in the conditions of 25, 40 and 50% oxygen ambient by sputtering method were annealed at 600, 700 and $800^{\circ}C$, respectively. It was found that the crystallinity and the surface morphology of $IrO_2$films affected the surface properties and electrical properties of SBT thin films prepared by the MOD method. With increasing temperature, the crystallinity and the roughness of $IrO_2$films were also increasing. This increasing of roughness degraded the surface properties and electrical properties of SBT films. We found an optimum condition of $IrO_2$films as bottom electrode for ferroelectric capacitor at 50% oxygen ambient and $600^{\circ}C$ annealing temperature. Electrical characterizations were performed by using$ IrO_2$bottom electrodes grown at an optimum conditions. The remanent polarization ($P_{r}$) of the Pt/SBT/$IrO_2$/$SiO_2$/Si structure was 2.75 $\mu$C/$\textrm{cm}^2$ at an applied voltage of 3 V. The leakage current density was $1.06${\times}$10^{-3}$ A/$\textrm{cm}^2$ at an applied voltage of 3 V.

• 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 $K^+$.

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.961-966
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• 1994

Oligomerization of phenylacetylene is catalyzed by $Rh(ClO_4)(CO)(PPh_3)_2$ (Rh-1), $[Rh(CO)(PPh_3)_3]ClO_4$ (Rh-2), $[Rh(COD)L_2]ClO_4 (L_2=(PPh_3)_2$, Rh-3; $(PPh_3)(PhCN)$, Rh-4; $(PhCN)_2$, Rh-5), $[Rh(C_3H_5)(Cl)(CO)(SbPh_3)_2]ClO_4$ (Rh-6), $[Ir(COD)L_2]ClO_4 (L_2=(PPh_3)_2$, $Ir-1; (PPh_3)(PhCN)$, $Ir-2; (PhCN)_2$, Ir-3; (AsPh_3)(PhCN)$, $Ir-4; Ph_2PCH_2CH_2PPh_2$, Ir-5; COD, Ir-6 and 2,2'-dipyridyl, Ir-7), $Ir(ClO_4)(CO)(PPh_3)_2$, $Ir-8, [Ir(PhCN)(CO)(PPh_3)_2]ClO_4$, Ir-9 to produce dimerization products, 1,3-diphenylbut-1-yn-3-ene, 1, (E)-1,4-diphenylbut-1-yn-3-ene, 2 and (Z)-1,4-diphenylbut-1-yn-3-ene, 3, and cyclotrimerization products, 1,3,5-triphenylbenzene, 4 and 1,2,4-triphenylbenzene, 5. Product distribution of the oligomers varies depending on various factors such as the nature of catalysts, reaction temperature, counter anions and excess ligand present in the reaction mixtures. Increasing reaction temperature in general increases the yield of the cyclotrimerization products. Exclusive production of dimer 1 and trimer 4 can be obtained with Ir-1 at 0 $^{\circ}$C and with Ir-2 in the presence of excess PhCN (or $CH_3CN$) at 50 $^{\circ}$C, respectively. Dimer 2 (up to 81%) and trimer 5 (up to 98%) are selectively produced with Rh-1 at 50 and 100 $^{\circ}$C respectively. Production of 3 is selectively increased up to 85% by using $PF_6$- salt of $[Ir(COD)(PPh_3)_2]$+ at 25 $^{\circ}$C. Addition of $CH_3I$ to Rh-1 produces $CH_3PPh_3^+I-$ and increases the rate of oligomerization(disappearance of phenylacetylene). Among the metal compounds investigated in this study, Ir-1 catalyzes most rapidly the oligomerization where the catalytically active species seems to contain lr(PPh3)2 moiety. The stoichiometric reaction of phenylacetylene wth Ir-9 at 25 $^{\circ}$C quantitatively produces hydridophenyl-ethynyl iridium(III) complex, $[lr(H)(C{\equiv}CPh)(PhCN)(CO)(PPh_3)_2]ClO_4$ (Ir-11), which seems to be an intermediate for the oligomerization.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.05a
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• pp.92-92
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• 1998

• Analytical Science and Technology
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• v.18 no.2
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• pp.120-129
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• 2005

Volatile organic compounds (VOCs) have been recognized as major contributor to air pollution. The catalytic oxidationis is one of the most important processes for VOCs destruction due to the possibility getting high efficiency at low temperature. In this study, monometallic Pt, Ir and bimetallic Pt-Ir were supported to $TiO_2$. In order to distribute metals uniformly, $H_2O-H_2$ treatment method was used. Xylene, toluene and MEK were used as reactants. The monometallic or bimetallic catalysts were prepared by the excess wetness impregnation method and characterized by XRD, XPS, and TEM analysis. Pt catalyst showed higher conversion than Ir catalyst and Pt-Ir bimetallic catalyst showed the highest conversion. The catalysts prepared by $H_2O-H_2$ treatment had better VOC's conversion than that of nothing treatment. In the VOCs oxidation, Pt-Ir bimetallic catalysts had multipoint active sites, so it improved the range of Pt metal state. Therefore, bimetallic catalysts showed higher conversion of VOCs than monometallic ones. $H_2O-H_2$ treatment effected an uniform distribution of Pt particles. In VOCs oxidation was found to follow first order reaetion kinetics. The activation energy of $H_2O-H_2$ treatment catalysts was lower than that of untreated ones. In this study, the a small amount of Ir was used with Pt to promote the oxidation conversion of VOCs.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.552-556
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• 2007

In this study, noble metals (Pd, Ru, Ir) were supported to $TiO_2$ catalyst. In order to distribute metals uniformly, $H_2O-H_2$ pretreatment technique was used. Xylene, toluene, and MEK were used as reactants. The monometallic or bimetallic catalysts were prepared by the excess wetness impregnation method and were characterized by XRD, and XPS analysis. Pd-Ru, Pd-Ir bimetallic catalysts had multipoint active sites which improved the range of Pd metal state. Bimetallic catalysts had a higher conversion of VOCs than that of monometallic one. The effect of $H_2O-H_2$ pretreatment technique was the enhancement of uniform distribution of Pd particles and promotion of catalytic efficiency. In this study, addition of Ru and Ir metals to Pd promoted oxidation conversion of VOCs. In addition, $H_2O-H_2$ pretreatment promoted removal efficiency of VOCs on the $TiO_2$ support.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.1
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• pp.17-22
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• 2003

The experimental FT-IR spectra and DTA curves of the $PbO-Bi_2O_3-B_2O_3-SiO_2$ glasses have been investigated. The composition ratio dependence of glass transition temperature showed that the structure of this glass system changes at 60 mol% $Bi_2O_3$. We have observed that the FT-IR spectra of the investigated samples with high bismuth content are dominated by bands associated to the structural units of the heaviest cation, $Bi^{3+}$ and the boron atoms in the treated samples are three and four coordinated even for very high $Bi_2O_3$ content. The low intensity of these non-bridging oxygen bands, for high PbO content glasses, can be attributed to the strong network-forming roles of PbO. The glasses absorption bands exhibited a greater change in intensities on crystallization.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.582-585
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• 2011

In this study, surface-adsorbed species of 1,2-dichlorobenzene (1,2-DCB) on mesoporous $V_2O_5/TiO_2$ catalysts synthesized by spray pyrolysis were investigated through the adsorption/desorption performed using in situ FT-IR cell. Also, the comparison of adsorbed species with $TiO_2$ and $V_2O_5/TiO_2$ synthesized by the incipient wetness was carried out.

• Journal of the Korean Chemical Society
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• v.45 no.5
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• pp.442-447
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• 2001

The charge-transfer compound (OMTTF)AuCl$_4$ was prepared from the direct reaction of octamethylenethiafulvalene (OMTTF) with HAuCl$_4{\cdot}xH_2$O in THF. (OMTTF)$_2PtCl_4$, (OMTTF)_2IrCl_6{\cdot}2H_2$O, and (OMTTF)Os$Cl_5{\cdot}THF$ were also formed using $H_2PtCl_6{\cdot}xH_2O$, $H_2IrCl_6{\cdot}xH_2O$ and $H_2OsCl_6$, respectively. The prepared compounds were characterized by magnetic (EPR, magnetic susceptibility), spectroscopic (IR, UV-Vis), electrochemical (CV) methods, and the powdered electrical conductivity measurement. The powdered electrical conductivities at room temperature were ~$10^{-7}S{\cdot}cm^{-1}$. The experimental results show that $OMTTF^+$ monocation radicals exist in all of the prepared compounds. The redox potential of OMTTF supports that $OMTTF^+$ is relatively stable. The magnetic properties indicate that there are significant magnetic interactions between the localized odd electrons on the central metal (Ir and Os) ions and the odd electrons resided on $OMTTF^+$ cation radicals in both (OMTTF) $_2IrCl_6{\cdot}2H_2O$ and (OMTTF)$OsCl_5{\cdot}THF$.