ZnO-free Inverted Polymer Solar Cells Based on New Viologen Derivative as a Cathode Buffer Layer

ZnO를 대체 가능한 새로운 Viologen 유도체가 적용된 역구조 고분자 태양전지

  • Kim, Youn Hwan (Department of Polymer Engineering, Pukyong National University) ;
  • Kim, Dong Geun (Department of Polymer Engineering, Pukyong National University) ;
  • Kim, Joo Hyun (Department of Polymer Engineering, Pukyong National University)
  • 김윤환 (부경대학교 고분자공학과) ;
  • 김동근 (부경대학교 고분자공학과) ;
  • 김주현 (부경대학교 고분자공학과)
  • Received : 2016.07.25
  • Accepted : 2016.08.25
  • Published : 2016.10.10


A new viologen derivative namely 1,1'-bis(3,4-dihydroxybutyl)-[4,4'-bipyridine]-1,1'-diium bromide (V-Pr-2OH) was synthesized and applied as a cathode buffer layer to inverted polymer solar cells (PSCs) based on the blend of PTB7 : $PC_{71}BM$. PSCs with the structure of ITO/V-Pr-2OH/PTB7 : $PC_{71}BM/MoO_3/Ag$ as the cathode buffer layer showed the power conversion efficiency (PCE) up to 7.28%, which is comparable to that of the PSCs with the structure of ITO/ZnO/PTB7 : $PC_{71}BM/MoO_3/Ag$ (7.44%) in the absence of V-Pr-2OH. This study demonstrates that a highly efficient PSCs without any high temperature heat treatment can be obtained.


Supported by : 한국에너지기술평가원


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