Polymer(Korea) (폴리머)

The Polymer Society of Korea (한국고분자학회)
권호 표지

Energy Transfer and Device Performance in Polymer Based Electrophosphorescent Light Emitting Diodes and Effect of Ligand Modification in the Optical and Electrical Properties of Phosphorescent Dyes

고분자 전기인광소자에서의 에너지 전이, 소자 특성 및 인광염료의 리간드 변화에 따른 광학적, 전기적 특성 변화

  • Lee Chang-Lyoul (School of Materials Science and Engineering, Center for Organic Light Emitting Diodes, Seoul National University) ;
  • Das R. R. (Samsung Advanced Institute of Technology) ;
  • Noh Young-Yong (Department of Materials Science and Engineering, Gwangju Institute of Science and Technology) ;
  • Kim Jang-Joo (School of Materials Science and Engineering, Center for Organic Light Emitting Diodes, Seoul National University)
  • 이창렬 (서울대학교 재료공학부) ;
  • ;
  • 노용영 (광주과학기술원 신소재공학과) ;
  • 김장주 (서울대학교 재료공학부)
  • Published : 2005.03.01
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Abstract

Electrophosphorescent light emitting diodes (LEDs) using phosphorescent dyes as triplet emitter, which incorporate a heavy metal atom to mix singlet and triplet states by the strong spin-orbit coupling, can achieve the theoretically $100\%$ internal quantum efficiency. In this paper, we report on the performance and the energy transfer mechanism of polymer based highly efficient electrophosphorescent LEDs. The effect of phase separation and aggregation to the energy transfer between polymer hosts and phosphorescent guests and performance of polymer electrophosphorescent LEDs were investigated. Finally, the effect of introducing substitute group and ligand modification of phosphorescent dyes on optical and electrical properties are reported.

전기인광소자(electrophosphorescent light emitting diodes)의 경우 인광염료내에 있는 중금속에 의해 효과적인 전자 스핀-궤도 결합(spin-orbit coupling)이 가능하며, 이로 인해 일중항 여기자뿐만 아니라 삼중항 여기자로부터 발광이 가능하므로 이론적으로 $100\%$ 내부발광효율을 얻을 수 있다. 본 논문에서는 지난 몇 년 동안 본 연구실에서 진행한 고분자 호스트를 사용한 고분자 전기인광소자의 특성 및 에너지 전이 메커니즘에 대하여 기술하였다. 또한 고분자 전기인광소자에서의 상분리 및 응집현상이 고분자 호스트와 게스트인 인광염료간의 에너지 전이와 소자 특성에 미치는 영향을 규명하였다. 마지막으로 인광염료의 리간드에 치환체 도입 및 리간드 변화에 따른 전이금속화합물의 광학적, 전기적 특성 변화에 대하여 연구하였다.

Keywords

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