Solvothermal synthesis of ZnO nanoparticles at low temperatures as cathode buffer layers for polymer solar cells with an inverted device structure

  • Jie Luo
  • Qian Liu
  • Yong Zhang
  • Wei Zhang
  • Zuyong Feng
  • Peiju Hu


Inverted polymer solar cells of the conventional poly(3-hexylthiophene) (P3HT):(6,6)-phenyl-C61butyric acid methyl ester (PC61BM) blend on indium tin oxide substrates were fabricated. By using mixed-solvent dispersed ZnO nanoparticles (NPs) as cathode buffer layer, device performances are improved obviously. ZnO NPs with a size of 3–5 nm synthesized by solvothermal synthesis at 65 °C show relatively wide photoluminescence peak of 300–650 nm. Based on Hansen solubility parameter theory, a mathematical method was applied to calculate the Hansen solubility parameters of bi-solvent system to disperse ZnO NPs and the proportion of each component in the mixed solvent. This excellent dispersion for ZnO NPs in the bi-solvent system has a important influence on the performance of the device. Compared to other methods of ZnO nanofilm fabrication, this method reveals a simple, convenient, moderate and effective way to manufacture the favorable buffer layer in organic solar cells.


Buffer Layer Power Conversion Efficiency Organic Solar Cell Polymer Solar Cell Zinc Acetate Dihydrate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We gratefully acknowledge the financial support of National Natural Science Foundation of China (No. 11304045), and Guangdong provincial science and technology projects (Grant No. 2013B090700006).


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Jie Luo
    • 1
  • Qian Liu
    • 1
  • Yong Zhang
    • 2
  • Wei Zhang
    • 1
  • Zuyong Feng
    • 1
  • Peiju Hu
    • 1
  1. 1.School of Physics and Optoelectronic EngineeringGuangdong University of TechnologyGuangzhouChina
  2. 2.Institute of Optoelectronic Materials and TechnologySouth China Normal UniversityGuangzhouChina

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