Electrostatic Self-Assembly Conjugated Polyelectrolyte-Surfactant Complex as an Interlayer for High Performance Polymer Solar Cells

Authors

  • Yi-Ming Chang,

    1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
    2. Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan
    Search for more papers by this author
  • Rui Zhu,

    Corresponding author
    1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
    • Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA.
    Search for more papers by this author
  • Eric Richard,

    1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
    Search for more papers by this author
  • Chun-Chao Chen,

    1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
    Search for more papers by this author
  • Gang Li,

    1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
    Search for more papers by this author
  • Yang Yang

    Corresponding author
    1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
    • Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA.
    Search for more papers by this author

Abstract

A simple method is demonstrated to improve the film-forming properties and air stability of a conjugated polyelectrolyte (CPE) without complicated synthesis of new chemical structures. An anionic surfactant, sodium dodecybenzenesulfonate (SDS), is mixed with cationic CPEs. The electrostatic attraction between these two oppositely-charged materials provides the driving force to form a stable CPE-surfactant complex. Compared with a pure CPE, this electrostatic complex is not only compatible with highly hydrophobic bulk-heterojunction (BHJ) films, e.g. poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester (P3HT:PCBM), but also works well with other low bandgap polymer-based BHJ films. Using this complex as a cathode interface layer, a high power conversion efficiency of 4% can be obtained in P3HT:PCBM solar cells together with improved stability in air. Moreover, ∼20% performance enhancement can also be achieved when the complex is used as an interlayer to replace calcium metal for low bandgap polymer-based BHJ systems.

Ancillary