In-depth considerations for better polyelectrolytes as interfacial materials in polymer solar cells

Yeo, Jun-Seok,Kang, Minji,Jung, Yen-Sook,Kang, Rira,Lee, Seung-Hoon,Heo, Youn-Jung,Jin, Sung-Ho,Kim, Dong-Yu,Na, Seok-In Elsevier 2016 Nano energy Vol.21 No.-

<P><B>Abstract</B></P> <P>We perform a comprehensive study to achieve better polyelectrolytes (PEs) as electron-transport layers (ETLs) in polymer solar cells (PSCs). Three well-known PEs – PFN, PEIE, and WPF – are chosen as model systems and investigated with variations in their backbone structures and the state of the amine functionalities on their side chains. Respectively optimized PSCs using the three PEs exhibit different cell-performances, mainly owing to the diode characteristics of built-in potential and recombination strength. To identify how such deviated device-performances correlate with the structural features of PEs, the modulated interfaces of ITO/PEs and PEs/active layer are studied in detail. It is found that conjugated backbones and larger counter-anions on side chains can promote the modulation of ITO work functions (WFs) and that a large amount of protonated amines on PEs is beneficial for junction properties with a subsequent active layer. Additionally, our results indicate that interfacial dipole and electrical doping between the PE and active layer, in addition to WF modulation of the ITO cathode, are important for device efficiency. Accordingly, with the aid of the molecular features of PEIE, PEIE-PSCs exhibit excellent device efficiency and stability compared with PFN- and WPF-PSCs. In the PTB7-th:PC<SUB>71</SUB>BM system, a remarkable power-conversion efficiency of 9.97% is achieved with a single PEIE ETL.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Chemical structure and performance of polyelectrolytes (PEs) in PSCs are correlated. </LI> <LI> Interfacial dipole and doping between PEs and active layer lead to efficient PSCs. </LI> <LI> PEIE-based PSCs have excellent device efficiency and high stability. </LI> <LI> Especially, in the PTB7-th system, encouraging efficiency of 9.97% is achieved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

In_xGa_1-xN/GaN 다중양자우물 구조의 광학적 성질 연구

김기홍,김인수,박헌보,배인호,유재인,장윤석,Kim, Ki-Hong,Kim, In-Su,Park, Hun-Bo,Bae, In-Ho,Yu, jae-In,Jang, Yoon-Seok 한국진공학회 2009 Applied Science and Convergence Technology Vol.18 No.1

$In_xGa_{1-x}N$/GaN 다중양자우물 구조의 EL 특성을 온도와 주입전류 변화에 따른 특성을 조사하였다 저전류와 고전류 주입시 EL 효율의 온도 의존 변화는 매우 다르게 나타나는데, 이러한 온도와 전류의 변화에 의한 독특한 EL 효율의 변화는 내부전기장의 존재 하에 순방향 바이어스에 기인한 외부전기장의 영향인 것으로 볼 수 있다. 그리고 $In_xGa_{1-x}N$/GaN 다중양자우물 구조에서 In 성비의 증가는 발광파장위치의 적색이동을 보였다. 15K에서 주입 전류의 증가에 따라 녹색 양자우물 구조는 80 meV와 청색 양자우물 구조는 22 meV의 청색 편이를 하였다. 이는 전류의 증가에 의해 단위 시간당 생성되는 캐리어 수가증가하게 되고 그에 따라 subband가 급격히 채워지는 band filling 현상이 일어나게 되어 짧은 파장에서 재결합이 증가하기 때문이다. 그리고 청색과 녹색 다중 양자우물구조의 짧은 파장 쪽으로의 편이 차이는 In 농도에 기인한 것으로 In 농도가 높으면 양자우물 깊이가 증가되어 더 강한 양자속박효과가 작용하여 캐리어 구속력이 증가하기 때문 것으로 볼 수 있다. Temperature and injection current dependence of electroluminescence(EL) spectral intensity of the $In_xGa_{1-x}N$/GaN multi-quantum wells(MQW) have been studied over a wide temperature range and as a function of injection current level. It is found that a temperature-dependent variation pattern of the EL efficiency under very low and high injection currents shows a drastic difference. This unique EL efficiency variation pattern with temperature and current can be explained field effects due to the driving forward bias in presence of internal(piezo and spontaneous polarization) fields. Increase of the indium content in $In_xGa_{1-x}N$/GaN multiple quantum wells gives rise to a redshift of 80 meV and 22 meV for green and blue MQW, respectively. It can be explained by carrier localization by potential fluctuation of multiple quantum well and MQW structures also shows a keen difference owing to the different indium content in InGaN/GaN MQW.

Preliminary assessment of correlation between T-lymphocyte responses and control of porcine reproductive and respiratory syndrome virus (PRRSV) in piglets born after in-utero infection of a type 2 PRRSV

Cha, Sang-Ho,Bandaranayaka-Mudiyanselage, Carey,Bandaranayaka-Mudiyanselage, Chandima B.,Ajiththos, Dharani,Yoon, Kyoung-Jin,Gibson, Kathleen A.,Yu, Ji-Eun,Cho, In-Soo,Lee, Stephen S.,Chung, Chungwon The Korean Society of Veterinary Science 2018 大韓獸醫學會誌 Vol.58 No.1

A preliminary study into the protective mechanisms of adaptive immunity against porcine reproductive and respiratory syndrome virus (PRRSV) in piglets (n = 9) born to a gilt challenged intranasally with a type-2 PRRSV. Immune parameters (neutralizing antibodies, $CD3^+CD4^+$, $CD3^+CD8^+$, $CD3^+CD4^+CD8^+$ T-lymphocytes, and PRRSV-specific interferon $(IFN)-{\gamma}$ secreting T-lymphocytes) were compared with infection parameters (macro- and microscopic lung lesion, and PRRSV-infected porcine alveolar macrophages ($CD172{\alpha}^+PRRSV-N^+\;PAM$) as well as with plasma and lymphoid tissue viral loads. Percentages of three T-lymphocyte phenotypes in 14-days post-birth (dpb) peripheral blood mononuclear cell (PBMC) had significant negative correlations with percentages of $CD172{\alpha}^+PRRSV-N^+\;PAM$ (p < 0.05) as well as with macroscopic lung lesion (p < 0.01). Plasma and tissue viral loads had significant (p < 0.05) negative correlations with $CD3^+CD4^+CD8^+$ T-lymphocyte percentage in PBMC. Frequencies of $CD3^+CD8^+$ and $CD3^+CD4^+$ T-lymphocytes in 14-dpb PBMC had significant negative correlations with of lymph node (p = 0.04) and lung (p = 0.002) viral loads. $IFN-{\gamma}$-secreting T-lymphocytes frequency had a significant negative correlation with gross lung lesion severity (p = 0.002). However, neutralizing antibody titers had no significant negative correlation (p > 0.1) with infection parameters. The results indicate that T-lymphocytes contribute to controlling PRRSV replication in young piglets born after in-utero infection.

정신분열병 환자에서 얼굴 영상의 작동기억 장애 : 기능자기공명영상연구

이창욱,김태석,주라형,박주미,박여진,김종진,전신수,배치운,김정진,이수정,이철,백인호 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.2

Objectives : Impaired processing of facial information is one of the broad ranges of cognitive deficits seen in patients with Schi-zophrenia. We aimed to elucidate the differences in brain activities involved in the process of facial working memory between schizophrenic patients and healthy comparison subjects. Methods : Twelve patients with schizophrenia were recruited along with twelve demographically matched healthy volunteers as a comparison group. Functional magnetic resonance imaging (fMRI) was used to assess cortical activities during the Perfor-mance of a 2-back working memory paradigm using images of neutral faces as mnemonic content. Rcsults : The patient group performed the tasks with reduced accuracy. Group analysis revealed that the left fusiform gyrus, the right superior frontal gyrus, the bilateral middle frontal gyri/insula, the left middle temporal gyrus, the precuneus, the quadrangular lobules and the vermis of cerebellum showed decreased cortical activities in the patient group. On the other hand, an increased level of activation in the lateral prefrontal cortex and the pahetal lobule was observed from the patient group, all in the right hemisphere. Conulusion : A decreased level of activity in the left fusiform gyrus among the patient group implicates inefficient processing of facial information. An increased level of activation in prefrontal and parietal neural networks from the patient group confirms earlier findings on the impaired working memory of patients with schizophrenia.

Al_(0.24)Ga_(0.76)As/GaAs HEMT 구조에서의 표면 광전압에 관한 연구

유재인,김종수,배인호,신영남,박성배 대구대학교 기초과학연구소 2000 基礎科學硏究 Vol.16 No.2

We report a surface photovoltage(SPV) study of Al_(0.24)Ga_(0.76)As/GaAs HEMT structure grown by molecular beam epitaxy. The energies of Eo transition for GaAs and Al_(0.24)Ga_(0.76)As were 1.41 and 1.71 eV, respectively. These values were in good agreement with photo reflectance(PR) measurement. As the frequency is increased from 25 to 55 Hz, the intensity of SPV signal is gradually reduced. Meanwhille, the intensity of SPV signal gradually increased as the temperature increased from 100 K to room temperature. From the former, the surface photovoltage of Al_(0.24)Ga_(0.76)As layer is 8.61 mV, which is about 1.4 times smaller than that of GaAs. This is due to influence of carrier mobility.

Intensifying the density of a horizontal electric field to improve light efficiency in a fringe-field switching liquid crystal display

Yu, In Ho,Song, Il Sub,Lee, Ji Youn,Lee, Seung Hee Institute of Physics [etc.] 2006 Journal of Physics. D, Applied Physics Vol.39 No.11

<P>The transmittance in fringe-field switching liquid crystal (LC) displays, which show a wide viewing angle, is dependent on the position along the electrode position. The reason for this is that the dielectric torque (and hence the twist angle) varies with position. This effect depends on the type of LC: a display using an LC with positive dielectric anisotropy has less transmittance than one with negative dielectric anisotropy. Furthermore, the transmittance decreases with decreasing cell gap. The difference between the LC types can be reduced and the transmittance can be improved greatly even for a low cell gap by optimizing the electrode structure to enhance the region of in-plane twist.</P>

철을 오염시킨 n-GaAs의Photoreflectance에 관한 연구

유재인,문영희,이동울,이정열,배인호,장광수 嶺南大學校 基礎科學硏究所 1998 基礎科學硏究 Vol.18 No.-

We investigated the variation of PR signals for n-GaAs surface treated with Fe as annealing method. The samples were annealed by isochronal(200∼600 ℃, 10 min) and isothermal(300 ℃, 10 ∼60 min) method. In PR signals measured from isochronal annealed samples, the rate of intensity decreasing for n-GaAs was 49%, and that for n-GaAs surface treated with Fe was 66%. We assumed that the large amount of decreasing intensity for Fe contaminated sample caused by decreasing carrier density due to increasing of ?? neutral acceptor at higher annealing temperature. In PR signals measured from isothermal annealed samples, the signals for annealed n-GaAs decreased with increasing annealing time, and the signals for n-GaAs surface treated with Fe continuously increased with increasing annealing time. It can be assumed that the increasing of PR intensity for Fe contaminated samples as annealing time caused by the diffusion of Fe atoms from the surface.

Area-selective atomic layer deposition of Al2O3 using inkjet-printed inhibition patterns and lift-off process

Yu Jun Ho,Cho Young–In,Lee Jae–Wook,Choi Kyung Hyun,Lee Sang–Ho 한국정보디스플레이학회 2023 Journal of information display Vol.24 No.3

Area-selective atomic layer deposition (AS-ALD) has been studied as an alternative method for metal oxide ALD film patterning in the microelectronics industry. To perform AS-ALD, area-deactivation or -activation processes should be implemented in advance using selective surface modification through a photography-based lift-off process and printing techniques. This study introduces a novel approach for Al2O3 AS-ALD using inkjet-printed inhibition patterns. ALD-inhibition patterns with two-layer structures of fluorocarbon (FC) thin film and photoresist (PR) were patterned by inkjet printing. Low surface energy FC thin films were used to block the Al2O3 nucleation and growth during the ALD process, and PR was patterned to easily remove ALD-inhibition patterns using a lift-off process. To demonstrate AS-ALD, an Al2O3 thin film approximately 10nm thick was deposited via an in-house built system with a multiple-slit gas source. The proposed AS-ALD method was evaluated for topological analysis using atomic force microscopy and surface composition analysis using a time of flight secondary ion mass spectrometry after Al2O3 deposition and a lift-off process. Finally, a 6nm thick Al2O3 film was selectively patterned by the lift-off process using an inkjet-printed 1.28 μm thick FC-covered PR inhibition pattern.

녹동균 세포외막 단백질 백신 CFC-1-101의 안정성 및 면역원성 검토 : 임상 제 Ⅰ/Ⅱa상 시험

장인진,김익상,유경상,임동석,김형기,신상구,장우현,박완제,이나경,정상보,안동호,조양제,안보영,이윤하,김영지,남성우,김현수 대한감염학회 1998 감염 Vol.30 No.3

목적 : 제일제당에서는 녹농균의 세포외막 단밸질을 유효성분으로 하는 백신인 CFC-101을 개발하였으며, 동물시험에서 이 백신의 안전성과 유효성을 입증하였다. 본 연구에서는 이 녹농균 백신의 인체에 대한 안전성과 면역원성을 평가하는 동시에 인체 접종시의 최적 투여 용량을 결정하기 위하여 제 I/Ⅱa상 임상시험을 수행하였다. 방법 : 건강한 성인 남자를 피험자로 선별하여 각 용량군에 백신투여자 6명, 위약투여자 2명을 배정하였다. 백신 투여군은 0.25mg, 0.5mg 또는 1.0mg 용량의 녹농균 백신을 7일 간격으로 3회에 걸쳐 근육주사 하였으며, 위약 투여군에게는 세포외막 단백질을 제외한 동일한 성분을 투여하였다. 백신접종 후 국소적 또는 전신적인 반응의 발생여부를 관찰하고, 혈액시료를 체취하여 백신의 역가와 유효성을 검정하였다. 결과 : 녹농균 백신 CFC-101은 모든 접종자에서 양호한 내약성을 보였다. 또한 0.5mg 과 1.0mg 백신 투여군에서는 100%의 항체양전율을 나타내었다. 생성된 항체는 녹농균 세포외막단백질에 특이성을 보였고, 녹농균 감염에 대해 방어효능이 있었다. 결론 : 이와같은 결과로부터 이 녹농균 백신은 인체에 안전하게 투여할 수 있으며, 높은 항체 생성능으로 감염방어 효능을 보이고 0.5mg과 1.0mg이 최적용량인 것으로 판단되었다. Background : We developed a Pseudomonas aeruginosa outer membrane protein(OMP) vaccine CFC-101, and the prophylactic efficacy of which has been demonstrated in animal models. In order to evaluate the safety and immunogenicity of the P. aeruginosa vaccine, we carried out a phase I/Ⅱa clinical trial in healthy male volunteers. Methods : Groups of eight volunteers, including two placebo subjects, were vaccinated intramuscularly with three doses of 0.25, 0.5 or 1.0 mg of the vaccine at one week intervals. Sings of systemic and local reactions observed after vaccination were recorded for each vaccinee for 5 days. Physical examinations were performed on days 0, 1, 7, 8, 14, 15, 21, and 42, and clinical laboratory tests were done on days 0, 3, and 21. Blood samples for assay of serum antibody levels were obtained up to 42 days after the first vaccination. Results : The vaccine was generally well tolerated by all vaccinees, showing no significant side effects. In the three dosage groups, all vaccinees, except one receiving the 0.25 mg dose, showed significant elevation in serum IgG antibody titers against the vaccine proteins, indicating 100% seroconversion in 0.5 and 1.0 mg groups. The human antibodies induced by the vaccine were specific for P. aeruginosa OMPs, as confirmed by western blot analysis and immunoprecipitation assays. The capacity of the human antisera to enhance opsonophagocytic killing activity by polymorphonuclear leukocytes and to confer protection against P. aeruginosa infections indicates that the antibodies elicited by the vaccine have protective efficacy. Conclusion : We conclude that the P. aeruginosa OMP vaccine is safe and effective for human use and its optimal dose to be 0.5 or 1.0 mg.

Fe가 오염된 GaAs에서의 Photoluminescence

김동렬,유재인,배인호,박성배,신영남 大邱大學校附設 基礎科學硏究所 1998 基礎科學硏究 Vol.15 No.2

Photoluminescence(PL) has been applied to characterize the transition in contaminated n-GaAs with Iron. The PL spectrum of the bulk n-GaAs at 15 K showed two peaks, one is the DAP peak located at 1.477 eV and the other is the Ga vacancy peak around 1.4973 eV. The PL spectrum of the Fe contaminated n-GaAs showed peak located at 1.4795 eV with broade the full with half maximum that relate with Fe acceptors. From temperature dependent PL intensity, activation energy E_(u) is determined to be 35 meV.