• 제목/요약/키워드: iodine doping

검색결과 15건 처리시간 0.029초

The 1320-nm Excited FT-Raman Spectra of Lightly Iodine-Doped trans-Polyacetylene

  • Kim, Jin-Yeol;Yukio Furukawa;Akira Sakamoto;Mitsuo Tasumi
    • Macromolecular Research
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    • 제10권5호
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    • pp.286-290
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    • 2002
  • The FT-Raman spectra of trans-polyacetylene films doped lightly with iodine were obtained with the 1320-nm laser line. The observed Raman bands are attributed to positively charged domains created by acceptor doping. The observed Raman wavenumbers of the V$_2$, (CC stretch), V$_3$, and V$_4$ bands (mixed of CC stretch and CH in-plan bending) of iodine-doped form are slightly higher than those of the corresponding bands of pristine trans-polyacetylene, whereas the contrary is the case for V$_1$, and (C=C stretch) of iodine-doped form. In particular, these upshifts of the V$_2$ and V$_3$ bands are distinguished from the downshifts of these bands in donor doping. The origin of doping induced Raman bands is discussed in terms of solitons and polarons.

Iodine Doping of Pentacene and its Electrical Properties

  • Rahim, Abdur;Lee, Young-Kyu;Lee, Chi-Young;Lee, Jae-Gab
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 춘계학술발표대회
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    • pp.238.2-238.2
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    • 2011
  • Organic thin film transistors (OTFTs) have been attracting considerable attention because of their potential use in low-cost, large area, electronic devices such as flexible displays, biochemical sensors, and smart cards. In past several years, gold/pentacene has been frequently used in OTFTs because of the high mobility of pentacene and the high work function of gold. To improve the performance of the OTFTs contact area doping of pentacene with p-doping materials are well known. In this work we demonstrated selectively contact area doping of pentacene with Iodine vapor. For effective doping elevated pentacene layer under the source-drain area was deposited and exposed to Iodine vapor. We got better electrical performance for elevated pentacene structure rather than planer structure with relatively high field-effect mobility.

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Efficient Carbonization of ABS Rubber via Iodine Doping

  • Park, Chiyoung;Kim, Chae Bin
    • Elastomers and Composites
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    • 제57권1호
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    • pp.9-12
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    • 2022
  • Herein, a facile approach for the development of effective and low-cost carbon precursors from acrylonitrile-butadiene-styrene (ABS) rubber is reported. ABS rubber with a negligible char yield can be converted into an excellent carbon precursor with approximately 54% char yield under a nitrogen atmosphere at 800℃ by simple iodine doping and subsequent heating at 110℃ under an inert atmosphere. The enhanced char yield is attributed to the improved intermolecular interactions between the ABS chains caused by the formation of covalent bonds between the butadiene segments, along with the newly developed charge-charge interactions and other indiscriminate radical-radical couplings. The charges and radicals involved in these interactions are also generated by iodine doping. We believe that this study will be useful for the development of low-cost carbon precursors.

Hole-Trapping in Iodine-Doped Pentacene Films at Low Temperatures

  • Yun, W.J.;Cho, J.M.;Lee, J.K.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.70-73
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    • 2006
  • Pentacene films, grown on polyethylene terephthalate (PET) substrates, were doped with Iodine. ESR measurements were made for the films in the temperature range of 100-300 K. Two regimes of doping stages were discernible: a light (intercalation) doping regime and a heavy doping regime. The light doping regime was concluded to be dominated by localized holes that were trapped at low temperatures, which indicated trap states near the valence band edge.

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N-Docosylquinolinium-TCNQ LB 막 의 Iodine Doping에 의한 물리적 특성 (A Physical Characteristics of the Iodine Doping of N-Docosylquinolinium-TCNQ Langmuir-Blodgett films)

  • 이창근;최강훈;김태완;신동명;강도열
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1994년도 추계학술대회 논문집
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    • pp.97-100
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    • 1994
  • The present paper is devoted to the physical and electrical characteristics of N-docosyl- quinolinium-TCNQ films compared with the films doped with I$_2$. Iodine affects the degree of charge transfer and the conductivity of the films. The UV-visible absorption spectra of the film doped with I$_2$ shows that the peak of I$_3$ which had electronic transition at 300∼350nm and (TCNQ-)$_2$ dimer absorption disappered. The in-plane electrical conductivity of the films doped with I$_2$ were 1.4${\times}$10$\sub$-6/S/cm, which is two orders of magnitude higher conductivity than undoped LB films. The film structural difference between Y and Z-type may cause the conductivity. Another possible reasons of the structural difference was the overlapping TCNQ anion radical in LB films.

$\sigma$-공액 고분자 poly(methyl-phenylsilyene)의 요오드 도핑효과 연구 (Iodine doping effect of $\sigma$ -conjugate poly(methyl-phenylsilene).)

  • 이철의;장재원
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.145-148
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    • 2000
  • In contrast to the $\pi$ -conjugated polymers which typically absorb light only in the visible spectral region, the $\sigma$-conjugated polymers can be used as efficient material absorbing light in the UV region. In this work, the electronic and optical properties of I$_2$-doped $\sigma$ -conjugated poly (methyl-phenylsilylene) (PMPSi) polymer were investigated. DC conductivity up to 1.2$\times$10$^{-4}$ S/cm was obtained by I$_2$-doping. In UV/Vis absorbance spectrum, a new peak was observed near 370 nm, which was explained by polaron model. The photoluminescence (PL) intensity decreased with increasing degree of I$_2$-doping, and the Infrared (IR) spectrum analysis revealed that the dopants are not directly coupled to the polymer, but effect motions of the methyl and phenyl groups.

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Vertically Aligned Carbon Film Synthesized from Magnetically Oriented Polyacetylene using Morphology Retaining Carbonization

  • Goh, Munju;Choi, Yong Mun
    • Carbon letters
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    • 제13권4호
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    • pp.226-229
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    • 2012
  • Polyacetylene (PA) films with vertically aligned fibril morphology were synthesized in homeotropic nematic liquid crystal (N-LC) solvent by using a magnetic field of 5 Tesla as an external perturbation. Scanning electron microscope (SEM) photographs indicated that the lengths of fibrils from the substrate were $5-35{\mu}m$, depending on polymerization time. Carbonization was carried out using iodine-doped PA film and a morphology-retaining carbonization method. From the SEM results, we confirmed that the vertical morphology of the PA remains unchanged even after carbonization at $800^{\circ}C$. The weight loss of the films due to carbonization at $800^{\circ}C$ is about 20% of the weight of the film before iodine doping. It is expected that vertically aligned carbon might be a precursor for preparing vertical graphite materials, which materials could be useful for electrochemical energy storage and cell electrodes.

a-Se에 첨가된 Iodine의 조성비 변화에 따른 X선 검출특성 연구 (The Study on X-ray Detection Characteristics of Radiation Detective Sensor with Changing Composition Ratio of Iodine in a-Se)

  • 차병열;강상식;이규홍;김재형;남상희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.399-402
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    • 2002
  • This paper is researched that electric characteristic of Digital x-ray radiography technique with changing composition ratio of Iodine. Dopant material, Iodine is evaporated with amorphous selenium. Thorugh the old papers say, doponted Iodine will be down the created trap level because of Arsenic dopant material in amorphous selenium. Arsenic material of Composition ratio in amorphous selenium is fixed with 0.3% and test sample is deposited composition of 30, 100, 300, 500, 700ppm with thermal evaporate system. Experimental measurement is performed by dark current and x-ray sensitivity in amorphous selenium based radition detector sensor. Fabricated test sample thickness is $30{\mu}m$ and injected voltage is $3{\mu}m$$6{\mu}m$$9{\mu}m$ to both electrode. Experimental results showed that the net charge of composition rate of 30ppm is 398.88 pc/mR/$cm^2$ very high. And increase of the Iodine composition ratio is tendency to the decrease of net charge. Doping changing composition of Iodine in amorphous selenium detector offered to basical information of amorphous selenium material.

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Viologen-TCNQ(2:2) LB막의 전기 및 자기적 특성에 관한 연구 (A study on the electrical and magnetic properties of Viologen-TCNQ(2:2) LB films)

  • 이용수;신동명;김태완;강도열
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 추계학술대회 논문집
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    • pp.195-198
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    • 1996
  • In conducting systems based on LB films, TCNQ derivatives have been extensively studied as electron acceptor molecules. We have investigated the optical, electrical, and magnetic properties of Viologen-(TCNQ ̄)$_2$LB films. In UV/visible absorption measurements, we have observed TCNQ ̄ peak at 380 nm and dimer peak at 620 nm. The electron spin resonance measurements infer that Viologen-(TCNQ ̄)$_2$LB film exhibits anisotropic properly. In other words, the LB film shows angular dependence. Iodine doping affects the degree of charge transfer and the conductivity of the films. The UV/visible absorption spectra of the LB film doped with I$_2$show peaks at near 400~430 nm and there is no dimer absorption peak. The in-plane electrical conductivity of the undoped film is approximately 4.2$\times$10$^{-6}$ S/cm.

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요오드가 도핑된 무금속 프탈로시아닌/산화아연계의 광기전력 효과(Ⅰ) (The Photovoltaic Effect of Iodine-Doped Metal Free Phthalocyanine/ZnO System (Ⅰ))

  • 허순옥;김영순;박윤창
    • 대한화학회지
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    • 제39권3호
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    • pp.163-175
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    • 1995
  • 무금속 프탈로시아닌/산화아연계의 감광호(photosensitization) 효율을 높이기 위하여 무금속 프탈로시아닌$(H_2Pc)$을 요오드로 도핑[$H_2Pc(I)_x$]하였다. $H_2Pc$ 결정형에 따른 $H_2Pc(I)_x$의 요오드 도핑 함량(x)은 원소 분석한 결과 $X-H_2Pc(I)_{0.92}$이고 ${\beta}-H_2Pc(I)_{0.96}$로 나타났다. $H_2Pc$에 대한 요오드의 도핑특성은 열무게 분석 (thermogravimetric analysis: TGA), UV-Vis, FT-IR 및 Raman 스펙트럼, 그리고 전자스핀 공명(electron spin resonance: ESR)으로 측정하였고, 산화아연에 대한 $H_2Pc(I)_x$의 흡착특성은 라만 스펙트럼 및 ESR로 조사하였다. TGA 분석 결과 $H_2Pc(I)_x$에 존재하는 요오드는 약 265$^{\circ}C$에서 완전히 없어졌고, 514.5 nm로 여기시킨 $H_2Pc(I)_x$$ZnO/H_2Pc(I)_x$의 Raman 스펙트럼에서는 주파수가 90~550 $cm^{-1}$에서 $I_3^-$의 특성 피크가 나타났다. 그리고 $ZnO/H_2Pc(I)_x$$g=2.0025{\pm}0.0005$에서 $ZnO/H_2Pc$보다 아주 강하고 좁은 ESR 신호가 나타났다. 요오드가 도핑된 $ZnO/H_2Pc(I)_x$의 감광화 효과는 요오드가 도핑되지 않은 $ZnO/H_2Pc$보다 높게 나타났다. 즉 670 nm에서 $ZnO/{\chi}-H_2Pc(I)_{0.92}$의 광기전력은 $ZnO/{\chi}-H_2Pc$보다 약 31배 높게 나타났고, ZnO/{\beta}-H_2Pc(I)_{0.96}$$ZnO/{\beta}-H_2Pc$보다 약 5배 높게 나타났다. $H_2Pc$ 결정형에 따른 $ZnO/H_2Pc(I)_x$의 감광화 효과는 670nm에서 $ZnO/{\chi}-H_2Pc(I)_{0.92}$$ZnO/{\beta}-H_2Pc(I)_{0.96}$보다 광기전력이 5배 높게 나타났다. 그러므로 $H_2Pc$가 요오드로 도핑됨에 따라 광전도성이 증가되어 산화아연에 대한 가시부에서의 감광화 효과가 향상되었다.

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