• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.647-652
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• 2009

A novel spiro-type host material, 5-[4-(1-naphthyl)phenyl]-spiro[fluorene-7,9'-benzofluorene] (BH-1PN) and three new dopants, namely, 5-[diphenylamino)phenyl]-spiro[fluorene-7,9'-benzofluorene] (BH-1TPA), 5-[4-(N-phenyl (m-tolyl)amino]-spiro[fluorene-7,9'-benzofluorene] (BH-1MDPA) and 5-[(N-phenyl)-2-naphthyl]amino-spiro[fluorene- 7,9'-benzofluorene] (BH-1NPA) were designed and successfully prepared using the Suzuki or amination reactions. The electroluminescence characteristics of BH-1PN as a blue host material doped with each of the blue dopants were evaluated. The structure of the device is ITO/DNTPD/NPB/BH-1PN:5% dopant/Alq3/Al-LiF. The device obtained from BH-1PN doped with diphenyl-[4-(2-[1,1;4,1]terphenyl-4-yl-vinyl)phenyl]-amine (BD-1) showed good color purity, efficiency, luminance, and current-density characteristics.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1355-1360
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• 2013

We have developed a new multifunctional material, 4,4',4"-tris(4-naphthalen-2-yl-phenyl)amine (2-TNPA), which can be used as a blue-emitting and hole-transporting material in organic light-emitting diodes (OLEDs), as well as a donor material in organic solar cells (OSCs) and an active material in organic thin-film transistors (OTFTs). The OLED device doped with 3% 2-TNPA shows a maximum current efficiency of 3.0 $cdA^{-1}$ and an external quantum efficiency of 3.0%. 2-TNPA is a more efficient hole-transporting material than 4,4'-bis[N-(naphthyl-N-phenylamino)]biphenyl (NPD). Furthermore, 2-TNPA shows a power-conversion efficiency of 0.39% in OSC and a field-effect mobility of $3.2{\times}10^{-4}cm^2V^{-1}s^{-1}$ in OTFTs.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.450-453
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• 2008

We synthesized a new HIL and HTL materials by using phenothiazinly moiety, 1,4-diphenothiazyl-benzene [DPtzB], 3',7',3",7"-tetrakis(N-phenyl-2-naphthylamine)-1,4-diphenothiazyl-benzene[PNA-DPtzB]. Synthesized materials exhibited high Tg in the range of $175\;-\;202^{\circ}C$. These values are much better than commonly used hole transporting materials (2-TNATA and NPB). The OLED device that used DPtzB as a HIL showed the highest efficiency of 4.31cd/A at $10mA/cm^2$.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.717-722
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• 2010

Two derivatives of star shaped compounds based on naphthylamine with symmetric trisubstituted benzene as core, methoxy and ethoxy as end substitutions are synthesized. The synthesized compounds are characterized by UV-visible, FT-IR and NMR spectrometric techniques. The electronic and thermal properties of the compounds are studied using cyclic voltametry (CV) and differential scanning calorimetry (DSC) respectively. The data's obtained have similarity with the arylamines that have been already used in optoelectronic devices. So these compounds are interesting materials for applications in such devices.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.4
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• pp.71-75
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• 2006

The yellow emitting OLED using GDI602:Rubrene(10%) material has been fabricated and characterized. In the device fabrication, 2-TNATA [4,4',4'-tris(2-naphthylphenyl-phenylamino)-triphenyl-amine] as a hole injection material and NPB[N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl -4,4'-diamine] as a hole transport material were deposited on the ITO(indium thin oxide)/glass substrate by vacuum evaporation. And then, yellow emission material was deposited using GDI602 as a host material and Rubrene(10%) as a dopant. Finally, small molecular OLED with the structure of $ITO/2-TNATA/NPB/GDI602:Rubrene(10%)/Alq_{3}/LiF/Al$ was obtained by in-situ successive deposition of $Alq_{3}$, LiF and Al as the electron transport material, electron injection material and cathode. The yellow OLED fabricated in our experiments showed the color coordinate of CIE(0.50, 0.49), the luminance of $2300\;Cd/m^{2}$ and the power efficiency of 0.7 lm/W at 10 V with the peak emission wavelength of 562 nm.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1475-1482
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• 2011

New spiro[benzo[c]fluorene-7,9'-fluorene] (SBFF)-based blue host materials, 9-phenyl-SBFF (BH-4P) and 5,9-diphenyl-SBFF (BH-6DP), were successfully prepared by spiro-formation of 9-phenyl-7H-benzo[c]fluoren-7-one with 2-bromobiphenyl via lithiation and reaction of 5,9-dibromo-SBFF with phenylboronic acid through the Suzuki reaction, respectively. Diphenyl-[4-(2-[1,1;4,1]terphenyl-4-yl-vinyl)-phenyl]-amine (BD-1) and N,N-diphenyl-N',N'-diphenyl-SBFF-5,9-diamine (BD-6DPA) were used as dopant materials. Blue OLEDs with the configuration ITO/N,N'-bis-[4-(di-m-tolylamino)phenyl]-N,N'-diphenylbiphenyl-4,4'-diamine (DNTPD)/bis[N-(1-naphthyl)-N-phenyl]benzidine (NPB)/host:5% dopant/SFC-137/Al-LiF were prepared from the two host materials doped with BD-1 and BD-6DPA dopants and the devices composed of BH-4P and BH-6DP doped with BD-6DPA showed blue EL spectra at 458 and 463 nm at 7 V and luminance efficiencies of 4.58 and 4.88 cd/A, respectively.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.929-932
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• 2014

We explored interfacial electronic structures in indium tin oxide (ITO)/DNTPD/N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB) layer stack in an OLED to clarify the real role of an aromatic amine-based hole injection layer, DNTPD. A hole injection barrier at the ITO/DNTPD interface is lowered by 0.20 eV but a new hole barrier of 0.36 eV at the DNTPD/NPB is created. The new barrier at the DNTPD/NPB interface and its higher bulk resistance serve as hole retardation, and thus those cause the operation voltage for the ITO/DNTPD/NPB to increase. However, it improves current efficiency through balancing holes and electrons in the emitting layer.