Frontiers of Materials Science

, Volume 12, Issue 2, pp 139–146 | Cite as

Influence of thermal annealing-induced molecular aggregation on film properties and photovoltaic performance of bulk heterojunction solar cells based on a squaraine dye

  • Pengpeng Zhang
  • Zhitian Ling
  • Guo Chen
  • Bin Wei
Research Article


Squaraine (SQ) dyes have been considered as efficient photoactive materials for organic solar cells. In this work, we purposely controlled the molecular aggregation of an SQ dye, 2,4-bis[4-(N,N-dibutylamino)-2-dihydroxyphenyl] SQ (DBSQ-(OH)2) in the DBSQ(OH)2:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend film by using the thermal annealing method, to study the influence of the molecular aggregation on film properties as well as the photovoltaic performance of DBSQ(OH)2:PCBM-based bulk heterojunction (BHJ) solar cells. Our results demonstrate that thermal annealing may change the aggregation behavior of DBSQ(OH)2 in the DBSQ(OH)2:PCBM film, and thus significantly influence the surface morphology, optical and electrical properties of the blend film, as well as the photovoltaic performance of DBSQ(OH)2:PCBM BHJ cells.


organic solar cells squaraine dye molecular aggregation film properties power conversion efficiency 


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This work was financially supported by the National Natural Science Foundation of China (Grant No. 61604093), the Shanghai Pujiang Program (16PJ1403300), the Natural Science Foundation of Shanghai (16ZR1411000), the Science and Technology Commission of Shanghai Municipality Program (17DZ2281700), and the Shanghai Software and integrated circuit industry development special funds (170401).

Supplementary material

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Supplementary information


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Copyright information

© Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Pengpeng Zhang
    • 1
  • Zhitian Ling
    • 1
  • Guo Chen
    • 2
  • Bin Wei
    • 2
  1. 1.School of Materials Science and EngineeringShanghai UniversityShanghaiChina
  2. 2.Key Laboratory of Advanced Display and System Applications (Ministry of Education)Shanghai UniversityShanghaiChina

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