Article
  • Charge-Carrier Transport Properties and Fluorescence Behaviors Depending on Charge Transport Complex of Organic Photoconductor Containing Liquid Crystal
  • Lee B, Jung SY, Moon DD
  • 액정을 함유하는 유기 광도전체의 전하 수송착체에 의한 Charge-Carrier수송 특성과 형광거동
  • 이봉, 정선영, 문두경
Abstract
Recently, it was found that the charge carrier transport properties are signficantly enhanced due to effective intermolecular π-orbital overlapping and low disorder of hopping sites caused by self-organization of liquid crystal molecules. In this study, the xerographic properties of a double-layer photoconductor doped with nematic liquid crystal, 4-pentyl-4`-cyanoterphenyl(5CT), as a charge-carrier transport material to enhance the charge-carrier mobility were investigated. From the results of measured surface voltage properties for the photoconductor doped with various concentrations of liquid crystal, 5CT, the initial voltage was found to increase with the concentration of 5CT and the dark decay decreased with the concentration of 5CT. The highest sensitivity was obtained at a specific concentration, 40 wt% 5CT. The fluorescence behavior of the carrier transport layer (CTL) was also investigated. It was found that the charge-carrier transport properties of the organic photoconductor depend on the charge-carrier transport properties of the complex. The TNF: 5CT (40 wt%) and OXD : 5CT (40 wt%) samples showed the highest sensitivity because the greatest charge transport complex was formed between the charge-carrier transport materials in these samples.

유기광도전체에 있어서의 액정은 종래의 분자 배향성을 가지지 않는 비정성 고체계와는 달리 분자 배향성을 가지기 때문에 분자 사이의 질서도가 높아지게 되고, charge-carrier의 hopping을 방해하는 hopping site의 공간적인 틈이 작아져 고 이동도의 특성을 가질 수 있다. 본 연구에서는 유기광도전체의 전하 수송층에 액정 5CT를 혼합하여, charge-carrier수송특성에 있어서의 액정 5CT의 영향을 관찰하였다. 액정 5CT를 함유한 유기광도전체는 액정의 혼합비가 증가함에 따라 초기전위는 증가하였으며, 암감쇄는 감소하는 경향을 나타내었다. 감도는 5CT를 TNF와 OXD 각각에 대하여 40 wt%로 혼합한 시료의 경우에 가장 우수하게 나타났다. 형광거동을 관찰한 결과, 이는 전하수송재료와 액정 5CT의 전하 수송착체에 의한 것으로, 액정 5CT를 TNF와 OXD 각각에 대하여 40 wt%로 혼합한 시료의 경우가 다른 시료들에 비해 전하 수송착체가 가장 잘 형성되어, 정공을 잘 수송하기 때문으로 나타났다.

Keywords: xerographic property; liquid crystal; organic photoconductor; fluorescence; charge transport complex

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  • Polymer(Korea) 폴리머
  • Frequency : Bimonthly(odd)
    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
  • 2022 Impact Factor : 0.4
  • Indexed in SCIE

This Article

  • 2001; 25(5): 719-727

    Published online Sep 25, 2001

  • Received on Mar 23, 2001