• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.469-472
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• 2008

New iridium complexes with 2-(3',5'-bis-trifluoromethylphenyl)-4-metoxypyridine [$(CF_3)_2ppyOMe$] were synthesized and characterized for blue phosphorescent materials. It was found that $Ir[(CF_3)_2ppyOMe]_2$(acac) gives blue emission at 471 nm with strong luminescence efficiency. We discuss the role played by electron withdrawing substituents and also how the ancillary ligand influences the emission peak.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.702-705
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• 2007

New heteroleptic tris-cyclometalated iridium complex, $Ir(ppy)_2(dpq-5CH_3)$, was prepared, where ppy and $dpq-5CH_3$ represent phenylpyridine and 2(5'-methyl)- 4-diphenylquinoline, respectively. The heteroleptic iridium complex shows high luminescence efficiency by the intramolecular energy transfer from the energy absorbing ppy ligands to the luminescent $dpq-5CH_3$ ligand leading to a decrease on quenching or energy deactivation.

• Journal of the Korean Ceramic Society
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• v.41 no.12 s.271
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• pp.880-883
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• 2004

Carbon nanofibers could be selectively formed at the groove area of the MgO substrate using microwave plasma-enhanced chemical vapor deposition system. Iridium metal was used as a catalyst layer for the formation of the carbon nanofibers. The growth direction of the carbon nanofibers was vertical to the substrate surface. The selectively grown iridium-catalyzed carbon nanofibers show around $1.8V/{\mu}m$ turn-on voltage and $1.0\;mA/cm^2$ field emission current density at $2.65\;V/{\mu}m$ in the field emission measurement.

• Korean Journal of Materials Research
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• v.16 no.1
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• pp.25-29
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• 2006

Vertical growth of iridium-catalyzed carbon nanofibers could be selectively grown on the MgO substrate using microwave plasma-enhanced chemical vapor deposition method. Growth positions of the iridium-catalyzed carbon nanofibers on the MgO substrate could be manipulated according to the applied bias voltage. At-150 V, the carbon nanofibers growth was confined only at the corner area of the substrate. Based on these results, we discussed the cause for the confinement of the vertically grown carbon nanofibers on the specific area of the MgO substrate as a function of the applied bias voltage.

• The Journal of Korean Society for Radiation Therapy
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• v.3 no.1
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• pp.11-18
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• 1989

Brachytherapy is known to be a good modality to achieve local control as a boost treatment following limited external irradiation, which may reduce the external beam related complication particularly in head and neck cancer. The authors developed iridium-192 ribbons recently to replace the radium needles in the field of brachytherapy. Total of 48 cases of head and neck and pelvic-perineal cancer patients had been treated with Ir-192 ribbons during last two years from October 1986 to September 1988, and the results were analyzed to assess the applicability of the fabricated sources. The conclusion is as follows; 1. Iridium implant resulted excellent tumor control effect in clinical application. 2. Iridium is superior than radium and cecium in brachytherapy because of easier to use and lesser exposure to the personnel. 3. Afterloading technique is useful to modify dose distribution, to expand treatment site and method, and to develop interstitial hyperthermia.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.1007-1010
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• 2011

$Ir(dpq/dpqx)_2$(przl-R) complexes were prepared and their electrochemical properties were investigated, where dpq, dpqx and przl-R represent 2,3-diphenylquinoline, 2,3-diphenylquinoxaline and N-phenyl-R-pyrazolonate derivatives, respectively. The iridium complexes containing dpq and dpqx as main ligands were reported to show red phosphorescence, and involvement of a pyrazolonate ancillary ligand in the iridium complexes led to high luminous efficiency for organic light-emitting diodes. In this study, we synthesized red phosphorescent iridium complexes containing a new pyrazolonate ancillary ligand and investigated the HOMOs, LUMOs and resulting electrochemical gaps of $Ir(dpq/dpqx)_2$(przl-R) by cyclic voltammetry. The emission wavelengths of the complexes at 600 - 640 nm were consistent with the gaps of 1.95 - 2.03 eV measured from reduction and oxidation potentials of the complexes.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1366-1370
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• 2013

A series of phosphorescent iridium(III) complexes 1-4 based on phenylpyrazole were synthesized and their photophysical properties were investigated. To evaluate their electroluminescent properties, OLED devices with the structure of ITO/NPB/mCP: 8% Iridium complexes (1-4)/TPBi/Liq/Al were fabricated. Among those, the device with 3 showed the most efficient white emission with maximum luminance of 100.6 $cd/m^2$ at 15 V, maximum luminous efficiency of 1.52 cd/A, power efficiency of 0.71 lm/W, external quantum efficiency of 0.59%, and CIE coordinates of (0.35, 0.40) at 15.0 V, respectively.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.528-533
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• 1995

Metallic iridium and rhodium powders prepared from the reactions of [M(COD)(PhCN)2]ClO4 (M=Ir(1), Rh(2); COD=1,5-cyclooctadiene) with hydrogen at room temperature in methylene chloride show catalytic activities for hydrogenation of arenes at room temperature under atmospheric pressure of hydrogen. Most substituents (CH3, COOH, NO2, CH2OH, CHO, OPh, OCH3, C=C, halogens and CH2Cl) on aromatic ring suppress the rate of the hydrogenation of the aromatic ring while the aromatic ring hydrogenation of phenol and 1,4-dihydroxobenzene is faster than that of benzene over these metallic powders. Hydrogenation of benzoic acid occurs only at the aromatic ring leaving the COOH group intact over iridium metal powders while benzoic acid is not hydrogenated at all over rhodium metal powders. Carbonyl, nitro, acetylenic and olefinic groups on an aromatic ring are hydrogenated prior to the aromatic ring hydrogenation. Hydrogenolysis of OH groups of phenol, benzyl alcohol and 1,4-dihydroxobenzene, and hydrodehalogenation of halobenzenes, benzyl halides and cinnamyl chloride also occur along with the hydrogenation of aromatic ring.

• Bulletin of the Korean Chemical Society
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• v.13 no.6
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• pp.627-631
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• 1992

The dihydrido iridium(Ⅲ) complex [$Ir(PPh_3)_2H_2(ac)_2$]$BF_4$ (ac=acetone) reacts with 2-phenylpyridine and 7,8-benzoquinoline to yield the C-H activated complexes [$Ir(PPh_3)_2$H(ac)(L)]$BF_4$ (L= phenylpyridine; 7,8-benzoquioline). The dihydrido iridium(Ⅲ) complex [$Ir(PPh_3)_2H_2(ac)_2$]$BF_4$ also reacts with triaklysilane via an oxidative addition reaction to yield the trihydrido iridium complexes [$Ir(PPh_3)_2H_3SiR_3$]$BF_4$ (R =Et and Ph). The structual configuration was studied by conventional spectroscopy.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.06a
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• pp.49-50
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• 1998