• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 1991년도 춘계학술대회 학술대회 프로그램
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• pp.8-12
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• 1991

탈질 박테리아를 이용한 사염화탄소의 분해 실험에서 electron donor의 공급이 중단되면 사염화탄소의 제거율이 낮아지고, 반면 electron acceptor의 주입이 중단되면 제거율이 높아졌다. 사염화탄소의 제거시 클로로폼이 생산되어 사염화탄소가 환원되고 있음을 보여 주었다. 이 결과는 사염화탄소가 일종의 electron acceptor로 작용하면서 전자를 얻기 위해 세포 내의 다른 electron acceptor와 경쟁한다는 가설을 뒷받침한다. 호기성 박테리아에 의해서도 실험조건하에서 상당량(25∼30%)의 사염화탄소가 제거되었다. Electron acceptor의 공급중단에는 영향을 받지 않았다. 그러나 사염화탄소의 제거와 함께 클로로폼이 형성되므로써 사염화탄소의 환원분해가 호기성 상태에서도 진행될 수 있음을 보여 주었다.

• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.569-572
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• 2003

The majority of dyes belong to the chromophoric class known as donor-acceptor systems. The essential structural feature of such systems is the presence of one or more electron donating groups conjugated to one or more electron withdrawing groups via an unsaturated bridge. The pyrazolin-5-one system is an effective electron acceptor residue, and can also act as a weak electron donor. In our experiments, the various symmetrical and unsymmetrical H-chromophores were synthesized in the indoxyl, imidazo[1,2-a]pyridin-2-one, pyrazolin-5-one, and pyridin-2,6-dione residues, resulting in cross-conjugated donor-acceptor systems. And the visible light absorption was then associated with the migration of electron density from the donor region of the molecule to the acceptor region. Also, it was useful to prepare related non-cross-conjugated donor acceptor chromophores by combining these residues with other electron donor or acceptor moieties. For convenience such chromophores are referred to as merocyanines.

• Environmental Analysis Health and Toxicology
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• 제6권3_4호
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• pp.149-154
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• 1991

Biodegradation of carbon tetrachloride (CTC) in denitrifying and aerobic columns was investigated under various conditions of electron-acceptor and electron-donor availability. CTC removal increased when the electron-acceptor (nitrate) injection was stopped in the denitrifying column; however, CTC remova1 decreased when electron donor (acetate) was deleted in the denitrifying and the aerobic column. Small fractions of the CTC removed appeared as chloroform, indicating that reductive dechlorination of CTC was occurring. The results from the denitrifying column support the hypothesis that CTC behaves as an electron acceptor that competes for the pool of available electrons inside the bacterial cells.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1098-1104
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• 2014

New electron deficient acceptor-acceptor-acceptor type of monomer unit composed of weak electron accepting benzimidazole and relatively strong electron accepting benzothiadiazole derivatives namely 4,7-bis(6-bromo-1-(2-ethylhexyl)-1H-benzo[d]imidazol-2-yl)benzo[c][1,2,5]thiadiazole (BBB) was synthesized. The Stille polycondensation of the newly synthesized BBB monomer with electron donating 2,6-bis(trimethyltin)-4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene (BDT) afforded donor-acceptor-acceptor-acceptor type of polymer namely 2,6-(4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene)-alt-4,7-bis(1-(2-ethylhexyl)-1H-benzo[d]imidazol-2-yl)benzo[c][1,2,5]thiadiazole (PBDTBBB). The opto-electrical studies revealed that the absorption band of PBDTBBB appeared in the range of 300 nm-525 nm and its highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels were positioned at -5.18 eV and -2.84 eV, respectively. The power conversion efficiency (PCE) of the polymer solar cell (PSC) prepared from PBDTBBB:PC71BM (1:2 wt %) blend was 1.90%.

• 대한화학회지
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• 제11권4호
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• pp.126-131
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• 1967

各 種 아민(triethylamine, diethylamine, pyridine, diphenylamine, dimethylaniline)과 各種 Electron Acceptor($CCl_4,\;ICl,\;I_2$)를 Hexane 溶媒 存在下에서 作用시킨 結果 各各 Charge Transfer Complex를 形成하였으나 그 形成能은 아민의 Basicity에 比例하였고 Electron Donor의 Polarity의 差가 클 때에는 다른 形式의 Complex를 形成함을 紫外線 吸收 分光法으로 確認하였다. Complex 形成能과 아민의 Basicity 및 Electron Acceptor의 Polarity의 關係를 論하였다.

• 폴리머
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• 제31권2호
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• pp.136-140
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• 2007

Carbazole(electron donor)그룹과 dinitrobenzene(electron acceptor)그룹을 이용하여 전하 이동 작용이 실세스퀴옥산/고분자 하이브리드의 형성 메커니즘으로서 작용할 수 있는지 살펴보는 연구를 진행하였다. 하이브리드 실험은 새롭게 합성된 Poly(carbazole-styrene) (PS/D)와 dinitrobenzyl silsesquioxane (Cube/A)의 톨루엔 용액을 혼합/캐스팅을 하여 만들어진 필름을 이용하였으며 상분리가 없는 투명한 하이브리드 필름이 일부 조건에서 얻어졌다. PS/D및 Cube/A의 $^1H-NMR$분석, 그리고 하이브리드 필름들의 UV 흡수 실험은 실세스퀴옥산에 의한 입체 장애 효과가 없는 조건에서는 acceptor와 donor가 1:1로 전하 이동 착물을 형성할 수 있지만, 상분리가 없는 투명한 실세스퀴옥산 하이브리드는 acceptor/donor의 비율이 0.7 : 1 이하에서 형성된다는 것을 보여주었다. 이 결과들은 또 실세스퀴옥산 한 분자 당 평균 4개의 전하 이동 착물이 형성된다는 하이브리드 나노 구조에 대한 정보도 제공하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.432.2-432.2
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• 2016

A new A-D-A type (Acceptor-Donor-Acceptor) conjugated based on pyridine-borane complex (Donor), non-boron fluorine (Donor) and 2,5-bis(alkyl)-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DPP) (Acceptor) were designed and synthesized via Pd-catalyzed Suzuki cross-coupling reaction. The synthesized boron based complex exhibited high electron affinity, which indicates deep HOMO energy levels and good visible absorption led to their use as donors in BHJ (bulk heterojunction) solar cells. Inverted devices were fabricated, reaching open-circuit voltage as high as 0.91eV. To probe structure-property relationship and search for design principle, we have synthesized pyridine-boron based electron donating small molecules. In this study, we report a new synthetic approach, molecular structure, charge carrier mobility and morphology of blended film and their correlation with the photovoltaic J-V characteristics in details.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.245.2-245.2
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• 2013

Solution processed organic photovoltaic devices have relatively less attention compared to polymer photovoltaic devices even though they have high possibility to be developed because they have both advantages of polymer and organic, such as solution processable, no synthetic batch dependence of photovoltaic performance, high purity and high charge carrier mobility as well as relatively high efficiency (~7%). In addition, solution processed organic photovoltaic devices have an advantage of easiness to study the relationship between the molecular structure and photovoltaic performance due to its simple structure. In this work, five isoindigo based low band gap donor-acceptor-donor (D-A-D) small molecules with different electron donating strength were synthesized for investigating the relationship between the molecular structure and photovoltaic performance, especially, investigating the effects of different electron donating effect of donor group in isoindigo backbone to photovoltaic device performance. The variation of electron donating strength of donor group strongly affected the optical, thermal, electrochemical and photovoltaic device performances of isoindigo organic materials. The highest power conversion efficiency of ~3.2% was realized in bulk heterojuction photovoltaic device consisted of the ID3T as donor and PC70BM as acceptor. This work demonstrates the great potential of isoindigo moieties as electron deficient units as well as guideline for synthesis of donor-acceptor-donor (D-A-D) small molecules for realizing highly efficient solution processed organic photovoltaic devices.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.795-802
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• 2012

Geminate electron-hole recombination in organic solids in the presence of a donor-acceptor heterojunction is studied by computer simulations. We analyze how the charge-pair separation probability in such systems is affected by energetic disorder of the media, anisotropy of charge-carrier mobilities, and other factors. We show that in energetically disordered systems the effect of heterojunction on the charge-pair separation probability is stronger than that in idealized systems without disorder. We also show that a mismatch between electron and hole mobilities reduces the separation probability, although in energetically disordered systems this effect is weaker compared to the case of no energetic disorder. We demonstrate that the most important factor that determines the charge-pair separation probability is the ratio of the sum of electron and hole mobilities to the rate constant of recombination reaction. We also consider systems with mobility anisotropy and calculate the electric field dependence of the charge-pair separation probability for all possible orientations of high-mobility axes in the donor and acceptor phases. We theoretically show that it is possible to increase the charge-pair separation probability by controlling the mobility anisotropy in heterojunction systems and in consequence to achieve higher efficiencies of organic photovoltaic devices.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1391-1396
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• 2014

In the present study, ten metal free non-linear optical (NLO) compounds have been designed. These compounds have designed by structural modification of (2-cyano-5-(4-(phenyl(4-vinylphenyl)amino)phenyl) penta-2,4-dienoic acid (TC4). Density functional theory was used for structure optimization and determination of photo-physical properties. These compounds contain triphenylamine as electron-donor and cyanoacrylic acid as acceptor. Five ${\pi}$-spacers are used to connect the donor and acceptor. Two auxiliary donors are also used to assist the donor. Results of this study indicate that stronger electron-donating auxiliary groups and longer ${\pi}$-conjugation enhance NLO response. Major absorption peaks of all systems were in the visible region. These absorption peaks are associated with the ${\pi}-{\pi}^*$ transitions of the entire molecule. From calculations it is clear that all system will be good NLO material. The present calculations will provide new ways for experimentalists to synthesize high-performance NLO material.