Electrical and optical characterizations of OSCs based on polymer/fullerene BHJ structures with LiF inter-layer

Polymer/fullerene/LiF inter-layer BHJ 유기태양전지의 광학 및 전기적 특성에 대한 연구

  • Song, Yoon-Seog (Department of Electronics Engineering, Dankook University) ;
  • Kim, Seung-Ju (Department of Electronics Engineering, Dankook University) ;
  • Ryu, S.O. (Department of Electronics Engineering, Dankook University)
  • 송윤석 (단국대학교 전자공학과) ;
  • 김승주 (단국대학교 전자공학과) ;
  • 류상욱 (단국대학교 전자공학과)
  • Received : 2011.01.14
  • Accepted : 2011.02.28
  • Published : 2011.03.31

Abstract

In this study, we have investigated the power conversion efficiency of organic solar cells utilizing conjugated polymer/fullerene bulk-hetero junction(BHJ) device structures. We have fabricated poly(3-hexylthiophene)(P3HT), poly[2methoxy-5-(3',7'-dimethyloctyl-oxy)-1-4-phenylenevinylene] as an electron donor, [6,6]-phenyl $C_{61}$ butyric acid methylester(PCBM-$C_{61}$)as an electron acceptor, and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS) used as a hole injection layer(HIL), after fabricated active layer, between active layer and metal cathode(Al) deposited LiF interlayer(5 nm). The properties of fabricated organic solar cell(OSC) devices have been analyzed as a function of different thickness. The electrical characteristics of the fabricated devices were investigated by means J-V, fill factor(FF) and power conversion efficiency(PCE). We observed the highest PCEs of 0.628%(MDMO-PPV:PCBM-$C_{61}$) and 2.3%(P3HT:PCBM-$C_{61}$) with LiF inter-layer at the highest thick active layer, which is 1.3times better than the device without LiF inter-layer.

Keywords

References

  1. J. H. Burroughes, D. D. C. Bradley, A. R. Brown, R. N. Marks, K. Mackay, R. H. Friend, P. L. Burns & A. B. Holmes, "Light-emitting diodes based on conjugated polymers", Nature, Vol. 347, pp. 539-541, 1990. https://doi.org/10.1038/347539a0
  2. J. Krumm, E. Eckert, W. H. Glauert, A. Ullmann, W. Clemens, "A Polymer Transistor Circuit Using PDHTT", IEEE Electron Device Letters, Vol. 25, pp. 399-401, 2004. https://doi.org/10.1109/LED.2004.829669
  3. C. J. Drury, C. M. J. Mustsaers, C. M. Hart, M. Matters, D. M. de leeuw, "Low-cost all-polymer integrated circuits", Applied Physics Letters, Vol. 73, pp. 108-110, 1998. https://doi.org/10.1063/1.121783
  4. Y. Kim, K. Lee, N. E. Coates, D. Moses, T. Nguyen, M. Dante, A. J. Heeger, "Efficient Tandem Polymer Solar Cells Fabricated by All-Solution Processing", Science, Vol. 317, pp. 222, 2000.
  5. S. Forrest, P. Burrows, M. Thompson, "The dawn of organic electronics", IEEE Spectrum, Vol. 37, pp. 29-34, 2000. https://doi.org/10.1109/6.861775
  6. N. Serdar Sariciftci, A. J. Heeger, "Handbook of organic Conductive Molecules and Polymers", Wiley, New york, Vol. 1(Ed:H. S. Nalwa), 1997.
  7. G. Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, "Polymer Photovoltaic Cells:Enhanced Efficiencies via a Network of Internal Donor-Acceptor heterojunctions", Science, Vol. 270, pp. 1789-1791, 1995. https://doi.org/10.1126/science.270.5243.1789
  8. Christoph J. Brabec, N. Serdar Sariciftci, Jan C. Hummelen, "Plastic Solar Cells", Advanced functional materials, Vol. 11, pp. 15-26, 2001. https://doi.org/10.1002/1616-3028(200102)11:1<15::AID-ADFM15>3.0.CO;2-A
  9. L. Smilowitz, N. S. Sariciftci, R. Wu, C. Gettinger, A. J. Heeger, F. Wudl, "Photoexcitation spectroscopy of conducting-polymer-C60 composites:Photoinduced electron transfer", The American Physical Society, Vol. 47, pp. 835-842, 1993.
  10. H. Y. Chen, J. Hou, S. Zhang, Y. Liang, G. Yang, Y. Yang, L. Yu, Y. Wu, and G. Li, "Polymer solar cells with enhanced open-circuit voltage and efficiency," Nature Photonics, Vol. 3, pp. 649-653, 2009. https://doi.org/10.1038/nphoton.2009.192
  11. M. Drees, R. M. Davis and J. R. Heflin, "improved morphology of polymer-fullerene photovoltaic devices with thermally induced concentration gradients", Journal of applied physics, Vol. 97, pp. 036103-1-3, 2005. https://doi.org/10.1063/1.1845574
  12. H. Hoppe, T. Glatzel, M. Niggemann, W. Schwinger, F. Schaeffler, A. Hinsch, M. Chu. L. Steiner and N. S. Sariciftci, "Efficiency limiting morphological factors of MDMO-PPV:PCBM plastic solar cells", Thin solid films, Vol. 587, pp. 511-512, 2006
  13. H. Sirringhaus, P. J. Brown, R. H. Friend, M. M. Nielsen, K. Bechaard, B. M. W. Langeveld-Voss, A. J. H. Spiering, R. A. J. Janssen, E. W. Meijer, P. Herwig and D. M. de leeuw, "Two-dimensional charge transport in self-organized, high-mobility conjugated polymers", Nature, Vol. 401, pp. 685-688, 1999. https://doi.org/10.1038/44359
  14. G. Wang, J. Swensen, D. Moses and A. J. Heeger, "Increased mobility from regioregular poly(3-hexylthiophene) field-effect transistors", Journal of applied physics, Vol. 95, pp. 316-322, 2004 https://doi.org/10.1063/1.1630693
  15. Cugolar, U. Giovanella, P. D. Gianvincenzo, F. Bertini, M. Catellani and S. Luzzati, "Thermal characterization and annealing effects of polythiophene/fullerene photoactive layers for solar cells", Thin solid films, Vo. 489, pp. 511-512, 2006.
  16. M. Lenes, L. J. A. Koster, "Thickness dependence of the efficiency of polymer:fullerene bulk heterojunction solar cells", Applied physics letters, Vol. 88, pp. 243502-1-3, 2006 https://doi.org/10.1063/1.2211189
  17. Christoph J. Brabec, Sean E. Shaheen, Christoph Winder, N. Serdar Sariciftci, Patrick Denk, "Effect of LiF/metal electrodes on the performance of plastic solar cells", Applied physics letters, Vol. 80, pp. 1446988-1-3, 2002.