• 제목/요약/키워드: Electron transport

검색결과 987건 처리시간 0.024초

Effect of Morphology on Electron Transport in Dye-Sensitized Nanostructured $TiO_2$ Films

  • Park, Nam-Gyu;Jao van de Lagemaat;Arthur J. Frank
    • Journal of Photoscience
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    • 제10권2호
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    • pp.199-202
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    • 2003
  • The relationship between the morphology of nanostructured TiO$_2$ films and the photo-injected electron transport has been investigated using intensity-modulated photocurrent spectroscopy (IMPS). For this purpose, three different TiO$_2$ films with 5 ${\mu}{\textrm}{m}$ thickness are prepared: The rutile TiO$_2$ film with 500 nm-sized cluster-like spherical bundles composed of the individual needles (Tl), the rutile TiO$_2$ film made up of non-oriented, homogeneously distributed rod-shaped particles having a dimension of approximately 20${\times}$80 nm (T2), and the anatase TiO$_2$ film with 20 nm-sized spherically shaped particles (T3). Cross sectional scanning electron micrographs show that all of the TiO$_2$films have a quite different particle packing density: poorly packed Tl film, loosely packed T2 film and densely packed T3 film. The electron transport is found to be significantly influenced by film morphology. The effective electron diffusion coefficient D$_{eff}$ derived from the IMPS time constant is an order of magnitude lower for T2 than for T3, but the D$_{eff}$ for the Tl sample is much lower than T2. These differences in the rate of electron transport are ascribed to differences in the extent of interparticle connectivity associated with the particle packing density.ity.

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HTL:EML(DPVBi:NPB) 층의 조성비 변화에 따른 청색 유기 발광 소자 개발 (Development of Blue Organic Light-Emitting Diodes(OLEDs) Due to Change in Mixed Ratio of HTL:EML(DPVBi:NPB) Layers)

  • 이태성;이병욱;홍진수;김창교
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 춘계학술대회 및 기술 세미나 논문집 디스플레이 광소자
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    • pp.31-32
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    • 2008
  • The structure of OLEDs with conventional heterostructure consists of anode, hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, and cathode. NPB used as a hole transport layer and DPVBi used as a blue light emitting layer were graded-mixed at selected ratio. Interface at heterojunction between the hole transport layer and the elecrtron transport layer restricts device's stability. Mixing of the hole transport layerand the emitting layer removes abrupt interface between the hole transport. layer and the electron transport layer. The stability of OLED with graded mixed-layer developed in this study was improved.

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Electron Transport Properties of Zn(phen)q Compared with Alq3 in OLED

  • Kim, Byoung-Sang;Kim, Dong-Eun;Choi, Gyu-Chae;Park, Jun-Woo;Lee, Burm-Jong;Kwon, Young-Soo
    • Journal of Electrical Engineering and Technology
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    • 제4권3호
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    • pp.418-422
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    • 2009
  • We synthesized new electroluminescence materials [(1,10-phenanthroline)(8-hydroxyquinoline)] Zn(phen)q and investigated their electron transport properties. We used Zn(phen)q and $Alq_3$ for the conductive materials and measured their electron transport properties as a function of the organic layer thickness. The difference between Zn(phen)q and $Alq_3$ as electron transporting materials suggests that the electrical properties depends on the carrier injection.

Analysis of Electron Transport Coefficients in Binary Mixtures of TEOS Gas with Kr, Xe, He and Ne Gases for Using in Plasma Assisted Thin-film Deposition

  • Tuan, Do Anh
    • Journal of Electrical Engineering and Technology
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    • 제11권2호
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    • pp.455-462
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    • 2016
  • The electron transport coefficients in not only pure atoms and molecules but also in the binary gas mixtures are necessary, especially on understanding quantitatively plasma phenomena and ionized gases. Electron transport coefficients (electron drift velocity, density-normalized longitudinal diffusion coefficient, and density-normalized effective ionization coefficient) in binary mixtures of TEOS gas with buffer gases such as Kr, Xe, He, and Ne gases, therefore, was analyzed and calculated by a two-term approximation of the Boltzmann equation in the E/N range (ratio of the electric field E to the neutral number density N) of 0.1 - 1000 Td (1 Td = 10−17 V.cm2). These binary gas mixtures can be considered to use as the silicon sources in many industrial applications depending on mixture ratio and particular application of gas, especially on plasma assisted thin-film deposition.

An Overview Of Nanonet Based Dye-Sensitized Solar Cell (DSSC) In Solar Cloth

  • Othman, Mohd Azlishah;Ahmad, Badrul Hisham;Amat, Noor Faridah
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권6호
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    • pp.635-646
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    • 2013
  • This technical paper contains the information of the Dye-Sensitized Solar Cells (DSSC) working principal where diffusion mechanism acts as electron transport to absorb the sunlight energy to generate the electrical energy. DSSC is photo electrochemical cell that implements the application of photosynthesis process. The performance of electron transport in DSSC has been reviewed in order to enhance the performance and efficiency of electron transport. The improvement of the electron transport also discussed in this paper.

Low voltage organic light-emitting devices with new electron transport layer

  • Ha, Mi-Young;Kim, So-Youn;Moon, Dae-Gyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.679-682
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    • 2007
  • We have developed low voltage operating OLEDs with new electron transport layer. The device having a structure of ITO/2TNATA/HTL:Rubrene(1%)/HTL /new ETL/LiF/Al have been used. The voltage for achieving $1,000\;cd/m^2$ was 4.1 V, whereas the turn on voltage for the brightness of $1\;cd/m^2$ was 2.8 V. This high luminance at low operating voltage is caused by the high current density, resulting from high electron conduction property of the new electron transport layer.

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생쥐 간세포 Mitochondria의 전자전달계에 미치는 Chromium(VI)의 영향 (Effetcs of Hexavalent Chromium on the Mitochondrial Electron Transport System in Mouse Liver)

  • 부문종;유창규;최임순
    • Applied Microscopy
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    • 제17권1호
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    • pp.29-46
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    • 1987
  • To study hexavalent chromium effects on mitochondrial electron transport, the activities of electron transport enzymes and conformational change of mitochondria treated with $40{\mu}M$ of sodium dichromate ($Na_{2}Cr_{2}O_{7}\;2H_{2}O$) were investigated. And so were those of liver mitochondria isolated from mouse intraperitoneally injected with sodium dichromate, 40mg per kg body weight. On both treatment with chromium(VI), the activities of electron transfer enzymes (Complex I and IV) were increased to some extent and the ultrastructural transformation of mitochondria from a condensed to an orthodox conformation was inhibited under State IV respiration. These results represent' inhibitory effect of hexavalent chromium on electron transport without inhibiting electron transfer enzymes (Complex I and IV) in mitochondria. On intraperitoneal treatment with hexavalent chromium as sodium dichromate and trivalent chromium as chromic chloride, containing 37.5 mg of chromium per kg body weight, respectively, the activities of electron transfer enzymes of liver isolated from mouse with chromium(VI) was reduced, but that with chromium(III) was not affected. And with chromium(VI), all mice after 12 hours of treatment died, only after 6 hours survived. With chromium(III), however, all survived. This indicates that hexavalent chromium is more toxic than trivalent chromiumin mouse liver.

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다항근사 볼츠만 방정식에 의한 $CF_4$ 분자가스의 전자수송계수 해석 (The analysis of electron transport coefficients in $CF_4$ molecular gas by multi-term approximation of the Boltzmann equation)

  • 전병훈;박재준;하성철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.141-144
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    • 2001
  • An accurate cross sections set are necessary for the quantitatively understanding and modeling of plasma phenomena. By using the electron swarm method. we determine an accurate electron cross sections set for objective atoms or molecule at low electron energy range. In previous paper, we calculated the electron transport coefficients in pure $CF_4$ molecular gas by using two-term approximation of the Boltzmann equation. And by using this simulation method. we confirmed erroneous calculated results of transport coefficients for $CF_{4}$ molecule treated in this paper having 'C2v symmetry' as $C_{3}H_{8}$ and $C_{3}F_{8}$ which have large vibrational excitation cross sections which may exceed elastic momentum transfer cross section. Therefore, in this paper, we calculated the electron transport coefficients(W and $ND_L$) in pure $CF_4$ gas by using multi-term approximation of the Boltzmann equation by Robson and Ness which was developed at lames-Cook university, and discussed an application and/or validity of the calculation method by comparing the calculated results by two-term and multi-term approximation code.

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다항근사 볼츠만 방정식에 의한 CF$_4$분자가스의 전자수송계수 해석 (The analysis of electron transport coefficients in CF$_4$ molecular gas by multi-term approximation of the Boltzmann equation)

  • 전병훈;박재준;하성철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.141-144
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    • 2001
  • An accurate cross sections set are necessary for the quantitatively understanding and modeling of plasma phenomena. By using the electron swarm method, we determine an accurate electron cross sections set for objective atoms or molecule at low electron energy range. In previous paper, we calculated the electron transport coefficients in pure CF$_4$ molecular gas by using two-term approximation of the Boltzmann equation. And by using this simulation method, we confirmed erroneous calculated results of transport coefficients for CF$_4$ molecule treated in this paper having 'C2v symmetry'as C$_3$H$_{8}$ and C$_3$F$_{8}$ which have large vibrational excitation cross sections which may exceed elastic momentum transfer cross section. Therefore, in this paper, we calculated the electron transport coefficients(W and ND$_{L}$) in pure CF$_4$ gas by using multi-term approximation of the Boltzmann equation by Robson and Ness which was developed at James-Cook university, and discussed an application and/or validity of the calculation method by comparing the calculated results by two-term and multi-term approximation code.e.

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고휘도 녹색 인광 OLED 제작에서 전자수송층 처리 (Treatments of Electron Transport Layer in the Fabrication of High Luminous Green Phosphoresent OLED)

  • 장지근;김원기;신상배;신현관
    • 반도체디스플레이기술학회지
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    • 제7권3호
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    • pp.5-9
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    • 2008
  • New devices with structure of ITO/2TNATA/NPB/TCTA/CBP:7%Ir(ppy)$_3$/BCP/ETL/LiF/Al were proposed to develop high luminous green phosphorescent organic light emitting diodes and their electroluminescent properties were evaluated. The experimental devices were divided into two kinds according to the material ($Alq_3$ or SFC137) used as an electron transport layer (ETL). Luminous intensities of the devices using $Alq_3$ and SFC137 as electron transport layers were 27,500 cd/$m^2$ and 51,500 cd/$m^2$ at an applied voltage of 9V, respectively. The current efficiencies of both devices were similar as 12.6 cd/A under a luminance of 10,000 cd/$m^2$, while showed slower decay in the device with SFC137 as an ETL according to the further increase of luminance. Current density and luminance of the device with SFC137 as an electron transport layer were higher at the same voltage than those of the device with $Alq_3$ as an ETL.

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