• 전기학회논문지P
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• 제51권3호
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• pp.142-148
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• 2002

Considerable progress has been made in organic photorefractive materials, since the first observation of photorefractive phenomena from organic materials. Within recent years, a large number of organic photorefractive materials, especially amorphous materials, have been developed based on polymeric composites, fully functional polymers and the multi-functional chromophore approach. Among these organic photorefractive materials, some of them containing carbazole components as a charge transporting function have been demonstrated to exhibit high performance photorefractive effects. The carbazole building blocks with charge transporting function or multifunctions play a very important role in photorefraction. In this paper, it confirmed that acceptor-substituted carbazoles show the multifunctionality both of photoconductivity and electro-optic(EO) activity and photorefractive materials newly can be developed with acceptor-substituted carbazoles.

• Journal of Ginseng Research
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• 제17권2호
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• pp.139-144
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• 1993

The method for colorimetric determination of acidic polysaccharide from Panax ginseng was investigated. It is possible to apply the method of carbazole-sulfuric acid to determination of pectin, and also to measure the amount of pectin in the mixture of various high molemlu compounds such as starch. cellulose and gum, etc. When the method of carbazole-sulfuric acid was applied to determine the amount of acidic polysaccharide, optical density at 525 nm increased linearly with an increase in the concentration of pure acidic polysaccharide. Effective extraction temperature with water for the determination of the amount of ginseng acidic polysaccharide (GAP) was $80{\circ}C$. In order to separate or concentrate GAP it was appropriate to precipitate the extract only once with 80% ethyl alcohol. GAP was very stable at $100{\circ}C$ for 4 hrs in aqueous solution and between pH values of 5.0~ 12.0.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3903-3905
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• 2013

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1026-1029
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• 2003

Polycarbazole derivatives have been investigated for emitting materials of PLED. We synthesized two polymers containing carbazole chromophor, which are different from bonding position. We investigated the spectra of their absorption, photoluminescence, electroluminescence.

• Bulletin of the Korean Chemical Society
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• 제29권11호
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• pp.2270-2272
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• 2008

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2419-2425
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• 2007

New poly(cyclopenta[def]phenanthrene) (PCPP)-based conjugated copolymers, containing carbazole units as pendants, were prepared as the electroluminescent (EL) layer in light-emitting diodes (LEDs) to show that most of them have higher maximum brightness and EL efficiency. The prepared polymers, Poly(2,6-(4-(6-(Ncarbazolyl)- hexyl)-4-octyl-4H-cyclopenta[def]phenanthrene)) (CzPCPP10) and Poly(2,6-(4-(6-(N-carbazolyl)- hexyl)-4-octyl-4H-cyclopenta[def]phenanthrene))-co-(2,6-(4,4-dioctyl-4H-cyclopenta[def]phenanthrene)) (CzPCPP7 and CzPCPP5), were soluble in common organic solvents and used as the EL layer in light-emitting diodes (LEDs) of configuration with ITO/PEDOT/polymer/Ca/Al device. The polymers are thermally stable with glass transition temperature (Tg) at 77-100 °C and decomposition temperature (Td) at 423-457 °C. The studies of cyclic voltammetry indicated same HOME levels in all polymers, although the ratios of carbazole units are different. In case of PLEDs with configuration of ITO/PEDOT/CzPCPPs/Ca/Al device, The EL maximum peaks were around 450 nm, which the turn-on voltages were about 6.0-6.5 V. The maximum luminescence of PLEDs using CzPCPP10 was over 4400 cd/m2 at 6.5 V, which all of the maximum EL efficiency were 0.12 cd/A. The CIE coordinates of the EL spectrum of PLEDs using CzPCPP10 was (0.18, 0.08), which are quite close to that of the standard blue (0.14, 0.08) of NTSC.

• Bulletin of the Korean Chemical Society
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• 제34권2호
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• pp.399-405
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• 2013

Two series of new green phosphorescent polymers bearing a bis(2-phenyl-pyridine)iridium(III)(dibenzoylmethane) [$(ppy)_2Irdbm$] complex were designed and synthesized. Poly-carbazole (PCbz) derivative or polyfluorene with pendant carbazole groups (PFCbz) were employed as host polymers for the iridium complex. The iridium complex monomer was copolymerized with the host monomers using varying monomer ratios via a Yamamoto coupling reaction. Efficient energy transfer from host to dopant unit was observed by increasing the ratio of the iridium guest in the copolymers. Electroluminescent devices with the configuration ITO/PEDOT:PSS/polymer/BmPyPB/LiF/Al were fabricated and characterized. The phosphorescent polymers composed of the iridium complex guest and polyfluorene with carbazole pendants as a host performed better than the polymers composed of the same guest and the main chain polycarbazole host. A maximum external quantum efficiency of 0.73%, a luminous efficiency of 1.21 cd/A, and a maximum luminance of 372 $cd/m^2$ were obtained from a device fabricated using one of the synthesized copolymers.

• 폴리머
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• 제37권6호
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• pp.736-743
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• 2013

공액구조 고분자의 밴드갭을 줄이기 위하여 청색의 디페닐렌비닐렌을 치환기를 갖는 카바졸 단량체와 용해도 향상을 위해 옥틸기를 도입한 카바졸 공단량체를 합성하여 신규 공중합체를 제조하였다. Suzuki 커플링 중합으로 공중합체를 제조하고, 공중합체의 열적, 분광학적, 전기광학적 특성을 조사하여 고분자 유기발광 다이오드(PLED)의 발광층에의 사용가능성을 조사하였다. 용액상태에서 공중합체의 UV 최대 흡수 파장은 333~340 nm, PL 최대방출 파장은 409~464 nm를 보였으며, 상대양자효율은 최대 25.8%의 값을 보였다. 열중량분석 결과 $350^{\circ}C$까지 열안정성을 보이고, 필름형성이 용이하였으며, 공중합체를 발광층으로 사용한 PLED 소자에서 4.0 V에서 청색광을 나타내었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.73.2-73.2
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• 2010

Polymer solar cells (PSCs) have attracted considerable academic and commercial interest because of their unique advantages, such as the facile manufacture of low cost, flexibility, lightweight, and solution processibility. Recently, high-performance polymer solar cells made from a mixture of poly(2,7-carbazole) derivatives, PCDTBT, and [6,6]-phenyl C71 butyric acid methyl ester (PC70BM) have been reported, with maximum power conversion efficiency of 6.1%. In this work, we report new novel copolymers based on poly(2,7-carbazole) derivatives with a suite of electron-deficient moieties or electron-rich units. We systematically investigated the synthesis, thermal stability, as well as the optical and electrochemical properties of these polymers. Detailed synthetic scheme, optical, electrochemical, and photovoltaic properties of the copolymers will be presented.

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3437-3442
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• 2014

A well-known carbazole-based precursor (probe 1) was used for the detection of cysteine/homocysteine and fluoride. Probe 1 shows a "turn-on" response to cysteine/homocysteine and fluoride via enhancement in emission intensity at 442 nm and 462 nm respectively, in solutions and living cells. Furthermore, probe 1 behaves as a fluorescent molecular switch between cysteine/homocysteine and fluoride as the chemical inputs, which have been used for the development of a combinatorial logic circuit and a molecular keypad lock.