Correlation Between Crystal Structure and Properties in Polymer Solar Cells

고분자 태양전지의 결정구조와 특성의 상관성

  • Kim, Jung Yong (Department of Chemical Engineering and Materials Science, University of Minnesota)
  • 김정용 (미네소타대학교 화학공학과)
  • Received : 2007.10.15
  • Accepted : 2007.10.30
  • Published : 2008.02.28

Abstract

The bulk-heterojunction polymer solar cell based on regioregular P3HT (poly(3-hexylthiophene)) and PCBM (methanofullerene [6,6]-phenyl $C_{61}$-butyric acid methyl ester) was fabricated. Annealing effects on the crystal structure of polymer-fullerene blends as well as the UV-VIS electronic absorption spectroscopy were investigated. The correlation between the crystal organization of bulk-heterojunction film and the power conversion efficiency of solar cell was studied. Resultantly, the polymer solar cell annealed on $150^{\circ}C$ for 30 min, showed both the enhanced molecular interactions and the optimized crystal structure and displayed the power conversion efficiency of 3.2 %.

지역규칙성 폴리3핵실티오펜과 용해성 플러렌 블렌드로 이루어진 벌크이종접합 고분자 태양전지를 제작하였다. 고분자 블렌드 필름에 대한 열처리 효과가 필름의 결정 구조와 자외선/가시광선 흡수스펙트럼에 주는 영향을 조사하였다. 그 후, 열처리에 의한 필름의 결정구조와 태양전지 효율의 상관관계를 연구하였다. 그 결과, $150^{\circ}C$에서 열처리한 필름이 분자간 상호작용 및 결정성측면에서 최적이었으며, 이 때, 고분자 태양전지의 에너지 전환 효율은 3.2 %이었다.

Keywords

Acknowledgement

Supported by : 한국학술진흥재단

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