• 제목/요약/키워드: power absorption

검색결과 849건 처리시간 0.034초

Small Molecular Solar Cells toward Improved Efficiency and Stability

  • 김지환;김효정;정원익;김태민;이영은;김세용;김장주
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.73-73
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    • 2011
  • We will report a few methods to improve the efficiency and stability in small molecule based organic solar cells, including the formation of bulk heterojunctions (BHJs) through alternative thermal deposition (ATD), the use of a micro-cavity structure and interface modifications. By ATD which is a simple modification of conventional thermal evaporation, the thicknesses of alternative donor and acceptor layers were precisely controlled down to 0.1 nm, which is critical to form BHJs. The formation of a BHJ in copper(II) phthalocyanine (CuPc) and fullerene (C60) systems was confirmed by AFM, GISAXS and absorption measurements. From analysis of the data, we found that the CuPc|C60 films fabricated by ATD were composed of the nanometer sized disk shaped CuPc nano grains and aggregated C60, which explains the phase separation of CuPc and C60. On the other hand, the co-deposited CuPc:C60 films did not show the existence of separated CuPc nano grains in the CuPc:C60 matrix. The OPV cells fabricated using the ATD method showed significantly enhanced power conversion efficiency compared to the co-deposited OPV cells under a same composition [1]. We will also present by numerical simulation that adoption of microcavity structure in the planar heterojunction can improve the short circuit current in single and tandem OSCs [2]. Interface modifications also allowed us to achieve high efficiency and high stability OSCs.

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4불화탄소 플라즈마처리에 의한 폴리에스테르 직물의 발수가공 (Water Repellent Finish of Polyester Fabric Using Carbontetrafluoride Plasma Treatment)

  • 모상영;이용운;김태년;천태일
    • 한국염색가공학회지
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    • 제6권3호
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    • pp.27-36
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    • 1994
  • In order to produce a water repellent surface on polyester fabric, samples were treated in the atmosphere of $CF_4$ glow discharge plasma. The samples used in the study were ployester fabric and poyester film. The purpose of film treatment is for the comparison of hydrophobicity with fabric sample at same treatment condition. Radio frequency(13.56MHz) generator was used as electric source and its in put power is 100 Watt. Water repellency was evaluated by contact angle measurement. Result obtained are as follows. 1) Fiber interstice of original fabric was ana lysed as 0.43$\mu$m, and this value was sufficiently ideal for making water repellent fabric. 2) The most favorable setting position of substrate was the center area between two electrodes. 3) Fabric contact angle was higher than film contact angle at same treatment condition, and its difference was more than 50${\circ}$. And it was incapalbe of fabric contact angle measurement when the film contact angle was less than 90${\circ}$. because the fabric is susceptible to absorption of water by the capillary effect. 4) Fabric contact angle can not revealed the precise defferences of surface hydrophobicity, however, the film contact angle showed the real hydrophobic nature. 5) It was not sufficient method to evaluate the hydrophobicity of fabric surface by merely measure of the water contact angle. 6) It showed high water repellent nature at 0.06 torr of $CF_4$ plasma gas pressure and duration of 45 seconds treatment, and it can not be anticipated more improved nature if the pressure and duration of treatment time were increased.

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Phenothiazine계 전도성고분자의 합성 및 유기박막태양전지로의 적용 연구 (Synthesis and Photovoltaic Properties of Conducting Polymers Based on Phenothiazine)

  • 유한솔;박용성
    • 공업화학
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    • 제24권1호
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    • pp.93-98
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    • 2013
  • 본 연구에서는 고온 고압반응을 통하여 4종의 전도성 고분자 poly[(N-butyl-phenothiazine)-sulfide] (PBPS), poly[(N-hexyl-phenothiazine)-sulfide] (PHPS), poly[(N-decyl-phenothiazine)-sulfide] (PDPS), poly[(N-(2-ethylhexyl)-phenothiazine)-sulfide] (PEHPS)를 합성하였다. 각 단계의 합성된 화합물의 구조는 $^1H-NMR$을 통하여 확인하였고, UV-Vis, cyclic voltammetry, GPC를 이용하여 합성된 고분자의 물성을 확인하였다. PBPS, PHPS, PDPS, PEHPS의 최대흡수파장은 각각 338, 341, 340, 334 nm이었으며, 각 고분자의 광학적 밴드 갭은 3.11, 3.13, 3.16, 3.05 eV이었다. 유기박막태양전지로서의 적용가능성을 확인하기 위해 합성된 고분자를 전자 받개 물질인 $PC_{71}BM$과 블렌딩하여 ITO/PEDOT : PSS/polymer (PBPS, PDPS) : $PC_{71}BM$ (1 : 3, w/w)/$BaF_2$/Ba/Al 구조의 소자를 제작하였고, solar simulator로 광전변환효율을 측정하였다. PBPS의 광전변환효율은 0.076%이었고, PDPS의 광전변환효율은 0.136%이었다.

이산화탄소 5 ton/day 흡수분리 Pilot Plant 운전 특성 (The Operational Characteristics of CO2 5 ton/day Absorptive Separation Pilot Plant)

  • 오민규;박소진;한근희;이종섭;민병무
    • Korean Chemical Engineering Research
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    • 제50권1호
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    • pp.128-134
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    • 2012
  • 석탄화력 발전소의 연소 배가스를 시간당 1,000 $Nm^3$을 처리할 수 있는 이산화탄소 분리용 pilot plant를 설치하여 화학흡수제인 mono-ethanolamine(MEA)과 2-amino-2-methyl-1-propanol(AMP)를 이용해서 운전특성을 연소 배가스 유량과, 흡수용액 순환유량을 주 실험변수로 분석하였다. MEA 20 wt%를 기준으로 연소 배가스 유량이 100 $m^3/hr$ 감소할수록 이산화탄소 제거율이 평균 6.7% 증가하였으며 흡수용액 순환유량이 1,000 kg/hr 증가에 따라 이산화탄소 제거율은 약 2.8% 상승하였고 $110^{\circ}C$ 재가열기 온도에서 90% 이상의 이산화탄소 제거효율을 나타냈다. MEA가 AMP보다 높은 제거효율을 보였고 MEA(20 wt%) 실험에서 이산화탄소의 제거율이 75.5%인 ASPEN plus의 모사 결과보다 10% 높은 85.5%로 나타났다.

염수 전기분해와 연계한 이산화탄소의 전환 공정 연구 (A Study on a Process for Conversion of Carbon Dioxide through Saline Water Electrolysis)

  • 이동욱;이지현;이정현;곽노상;이수진;심재구
    • Korean Chemical Engineering Research
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    • 제55권1호
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    • pp.86-92
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    • 2017
  • 석탄 화력발전 연소 배가스에 포함된 이산화탄소를 염수의 전기분해를 통해 얻어진 가성소다와 반응시켜 중탄산나트륨, 염소, 수소 등을 생산하는 공정에 대하여 실험과 전산모사를 병행하였다. Bench 규모 공정을 디자인하여 가성소다에 의한 이산화탄소 전환 공정에 대하여 실험하였고 같은 공정을 공정 모델링을 통해 전산모사 하였다. 실험결과와 전산모사 결과의 비교를 통해 모델의 신뢰성을 확인하였고, 상용급 공정에 대한 모델링을 수행하였다. 상용급 공정에 대한 열 및 물질수지를 계산하였고 반응기내 온도분포와 $CO_2$ 흡수율을 도출하였다. 본 연구를 통해 온실가스 저감뿐만 아니라 $CO_2$ 전환을 통한 경제성까지 갖춘 본 공정에 대한 기술 신뢰성을 확보할 수 있을 것이다.

PRAM을 위한 Aux(Ge2Sb2Te5)1-x (x=0, 0.0110, 0.0323, 0.0625) 박막의 상변환 특성 (Phase Change Characteristics of Aux(Ge2Sb2Te5)1-x (x=0, 0.0110, 0.0323, 0.0625) Thin Film for PRAM)

  • 신재호;백승철;김병철;이현용
    • 한국전기전자재료학회논문지
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    • 제24권5호
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    • pp.404-409
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    • 2011
  • An amorphous $Ge_2Sb_2Te_5$ thin film is one of the most commonly used materials for phase-change data storage. In this study, $Au_x(Ge_2Sb_2Te_5)_{1-x}$ thin film amorphous-to-crystalline phase-change rate were evaluated in using 658 nm laser beam. The focused laser beam with a diameter <10 ${\mu}m$ was illuminated in the power (P) and pulse duration (t) ranges of 1-17 mW and 10-460 ns, respectively, with subsequent detection of the responsive signals reflected from the film surface. We also evaluated the material characteristics, such as optical absorption and energy gap, crystalline phases, and sheet resistance of as-deposited and annealed films. The result of experiments showed that the thermal stability of the $Ge_2Sb_2Te_5$ film is largely improved by adding Au.

Bi-directional energy transfer process in Er3+-Tm3+-codoped fluorozirconate glasses

  • Cho, Woon-Jo;Kim, Myong-Wook;Kim, Snag-Hyuck;Jo, Jae-Cheol;Choi, Sang-Sam
    • Journal of the Optical Society of Korea
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    • 제1권1호
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    • pp.5-9
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    • 1997
  • Energy transfer direction in $Er^{3+}-Tm^{3+}$-codoped fluorozirconate glasses has been studied. For $Er^{3+}-Tm^{3+}$-codoped glasses, the dependence of the green emission intensity on the pump power (Pex) of 800 nm has ranged from (Pex)$^2$ to (Pex)$^3$. From this multistep absorption, a 1.48 $\mu m$ emission from the $^3F_4{\rightarrow}^3H_4$ transition on Tm$^{3+}$ ion has been found to transfer into $^4I_{13/2}$, $^4I_{9/2}$ and $^4S_{3/2}$ on $Er^{3+}$ ion. In case of the 1.06 $\mu m$ pumping, the emissin ratio of $^3H_4$ level in $Tm^{3+}$ to $^4I_{13/2}$ in $Er^{3+}$ showed that the amount of the energy transfer from $Tm^{3+}$ into $Er^{3+}$ increased with the increasing concentration of $Tm^{3+}$ ion. Our two kinds of pumping scheme suggest that the direction of dominant energy transfer between $Er^{3+}$ and $Tm^{3+}$ should be dependent on whether the $^3F_4$ level resonates in $Tm^{3+}$ the level or not.

Synthesis and Photovoltaic Properties of Novel Ruthenium(II) Sensitizers for Dye-sensitized Solar Cell Applications

  • Ryu, Tae-In;Song, Myung-Kwan;Lee, Myung-Jin;Jin, Sung-Ho;Kang, Sun-Woo;Lee, Jin-Yong;Lee, Jae-Wook;Lee, Chan-Woo;Gal, Yeong-Soon
    • Bulletin of the Korean Chemical Society
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    • 제30권10호
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    • pp.2329-2337
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    • 2009
  • Three heteroleptic ruthenium sensitizers, Ru(L)($L^1)(NCS)_2$ [L = 4,4'-dicarboxylic acid-2,2'-bipyridine, Ru-T1: $L^1$ = (E)-2-(4'-methyl-2,2'-bipyridin-4-yl)-3-(thiophen-2-yl)acrylonitrile, Ru-T2: $L^2$ = (E)-3-(5'-hexyl-2,2'-bithiophen-5- yl)-2-(4'-methyl-2,2'-bipyridin-4-yl)acrylonitrile, and Ru-T3: $L^3$ = (E)-3-(5"-hexyl-2,2':5',2"-terthiophen-5-yl)-2- (4'-methyl-2,2'-bipyridin-4-yl)acrylonitrile)], were synthesized and used as photosensitizers in nanocrystalline dyesensitized solar cells (DSSCs). The introduction of the 3-(5-hexyloligothiophen-5-yl)acrylonitrile group increased the conjugation length of the bipyridine donor ligand and thus improved their molar absorption coefficient and light harvesting efficiency. DSSCs with the configuration of Sn$O_2$: F/Ti$O_2$/ruthenium dye/liquid electrolyte/Pt devices were fabricated using these Ru-$T1{\sim}T3$ as a photosensitizers. Among the devices, the DSSCs composed of Ru-T2 exhibited highest power conversion efficiency (PCE) of 2.84% under AM 1.5 G illumination (100 mW/$cm^2$).

Synthesis and Characterization of Organic Light-Emitting Copolymers Containing Naphthalene

  • Kim, Jung-Sik;Heo, Jun;Kang, Peng-Tao;Kim, Jin-Hak;Jung, Sung-Ouk;Kwon, Soon-Ki;Kim, Un-Kyung;Kim, Yun-Hi
    • Macromolecular Research
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    • 제17권2호
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    • pp.91-98
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    • 2009
  • Conjugated PPV-derived block copolymers containing 2-ethylhexyloxynaphthalene unit were synthesized and characterized in this study. The resulting polymers were soluble in common organic solvents and showed good thermal stabilities, The weight-average molecular weights ($M_w$) of the copolymers ranged from 246,000 to 475,000 with PDIs of $1.3{\sim}2.1$. The optical properties of these polymers, measured both in a chloroform solution and on a film, showed a maximum absorption at $405{\sim}476\;nm$ for Copolymers $I{\sim}VIII$. In the PL spectra, Copolymers $I{\sim}VIII$ showed maximum peaks at $510{\sim}566\;nm$. The HOMOs, LUMOs and band gaps of the PPV derivatives of Copolymers $I{\sim}VIII$ were $5.30{\sim}5.77$, $3.04{\sim}3.24$, and $2.5{\sim}2.2\;eV$, respectively, The multi-layered, light-emitting diodes of ITO/PEDOT/copolymers/LiF/Al exhibited turn-on voltages of $6{\sim}2.5\;V$ Copolymer VIII exhibited the maximum brightness of $3.657\;cd/m^2$. Particularly, Copolymer VII, with an identical composition of MEH-PPV and naphthalene-PPV, showed a maximum luminance efficiency and power efficiency of 2,63 cd/A and 1.06 lm/W, respectively.

분리대두단백질을 첨가한 쌀국수의 제면특성 및 개발 (Characteristics and development of Rice Noodle Added with Isolate Soybean Protein)

  • 박희경;이효지
    • 한국식품조리과학회지
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    • 제21권3호
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    • pp.326-338
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    • 2005
  • The purpose of this study was to investigate the effect of isolate soybean protein (ISP) and rice flour on the characteristics of rice noodles. As the levels of ISP and rice flour increased, water binding capacity, swelling power of rice noodle increased. In RVA, pasting temperature, Set back showed an increasing tendency with peak viscosity, holding viscosity, break down, final viscosity of rice noodle increased as the level of rice flour by decreasing. Peak time was not significant. The weight, water absorption and volume of the cooked noodles were decreased. The turbidity of rice noodle increased. The Hunter color L, a-values of the dried rice noodle decreased. Cooked rice noodle quality increased with by decreasing the level of rice flour level. B-values of dried rice noodle and cooked rice noodle increased. Texture profile analysis of cooked rice noodle showed an increase of hardness. Adhesiveness, cohesiveness of cooked rice noodles decreased with by decreasing the level of ISP and rice flour. Gumminess, springiness, chewiness were increased. Sensory evaluation, showed gloss was increased. Hardness and chewiness of the cooked ice noodles were increased. Adhesiveness was not significant. Color and overall- acceptability were increased. Relationship between sensory and mechanical examinations (The overall quality of sensory examination for gloss) had a negative correlation with the mechanical examination for b-value (p.0.05). Mechanical examination for b-value had a positive correlation of sensory evaluation for hardness, chewiness, which had negative correlation of sensory evaluation for color. Scanning Electron, Microscopes observation of rice noodle was showed that the size of the hole grown was increased with by increasing the level of rice flour. From the above results, the most advisable mixture ratio of rice noodle evaluation was can be derived as follows: 171g rice flour, 114g wheat flour, 15g soybean protein isolate, 120ml water, and 6g salt.