Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Wrinkles and deep folds as photonic structures in photovoltaics

Abstract

Some of the simplest light-harvesting systems in nature rely on the presence of surface structures to increase internal light scattering. We have extended this concept to increase the efficiencies of man-made solar energy harvesting systems. Specifically, we exploit the wrinkles and deep folds that form on polymer surfaces when subjected to mechanical stress to guide and retain light within the photo-active regions of photovoltaics. Devices constructed on such surfaces show substantial improvements in light harvesting efficiencies, particularly in the near-infrared region where light absorption is otherwise minimal. We report a vast increase in the external quantum efficiency of polymer photovoltaics by more than 600% in the near-infrared, where the useful range of solar energy conversion is extended by more than 200 nm. This method of exploiting elastic instabilities of thin, layered materials is straightforward and represents an economical route to patterning photonic structures over large areas to improve the performance of optoelectronics.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Morphological evolution of wrinkles to folds.
Figure 2: Photovoltaic performance of polymer solar cells.
Figure 3: Photon flux diagrams of the optical stacks on flat, wrinkled and composite surfaces.
Figure 4: Flexible polymer solar cells constructed on flat and wrinkled surfaces.

Similar content being viewed by others

References

  1. Nalwa, K. S., Park, J.-M., Ho, K.-M. & Chaudhary, S. On realizing higher efficiency polymer solar cells using a textured substrate platform. Adv. Mater. 23, 112–116 (2011).

    Article  Google Scholar 

  2. Garnett, E. & Yang, P. Light trapping in silicon nanowire solar cells. Nano Lett. 10, 1082–1087 (2010).

    Article  ADS  Google Scholar 

  3. Battaglia, C. et al. Nanomoulding of transparent zinc oxide electrodes for efficient light trapping in solar cells. Nature Photon. 5, 535–538 (2011).

    Article  ADS  Google Scholar 

  4. Tvingstedt, K., Zilio, S. D., Inganäs, O. & Tormen, M. Trapping light with micro lenses in thin film organic photovoltaic cells. Opt. Express 16, 21608–21615 (2008).

    Article  ADS  Google Scholar 

  5. Sergeant, N. P. et al. Design of transparent anodes for resonant cavity enhanced light harvesting in organic solar cells. Adv. Mater. 24, 728–732 (2011).

    Article  Google Scholar 

  6. Prodan, E., Radloff, C., Halas, N. J. & Nordlander, P. A hybridization model for the plasmon response of complex nanostructures. Science 302, 419–422 (2003).

    Article  ADS  Google Scholar 

  7. Luther, J. M., Jain, P. K., Ewers, T. & Alivisatos, A. P. Localized surface plasmon resonances arising from free carriers in doped quantum dots. Nature Mater. 10, 361–366 (2011).

    Article  ADS  Google Scholar 

  8. Henzie, J., Lee, M. H. & Odom, T. W. Multiscale patterning of plasmonic metamaterials. Nature Nanotech. 2, 549–554 (2007).

    Article  ADS  Google Scholar 

  9. Gao, H. et al. Broadband plasmonic microlenses based on patches of nanoholes. Nano Lett. 10, 4111–4116 (2010).

    Article  ADS  Google Scholar 

  10. Bowden, N. et al. Spontaneous formation of ordered structures in thin films of metals supported on an elastomeric polymer. Nature 393, 146–149 (1998).

    Article  ADS  Google Scholar 

  11. Pocivavsek, L. et al. Stress and fold localization in thin elastic membranes. Science 320, 912–916 (2008).

    Article  ADS  Google Scholar 

  12. Kim, P., Abkarian, M. & Stone, H. A. Hierarchical folding of elastic membranes under biaxial compressive stress. Nature Mater. 10, 952–957 (2011).

    Article  ADS  Google Scholar 

  13. Sun, Y. et al. Controlled buckling of semiconductor nanoribbons for stretchable electronics. Nature Nanotech. 1, 201–207 (2006).

    Article  ADS  Google Scholar 

  14. Khang, D.-Y., Jiang, H., Huang, Y. & Rogers, J. A. A stretchable form of single-crystal silicon for high-performance electronics on rubber substrates. Science 311, 208–212 (2006).

    Article  ADS  Google Scholar 

  15. Yu, C. et al. Stretchable supercapacitors based on buckled single-walled carbon-nanotube macrofilms. Adv. Mater. 21, 4793–4797 (2009).

    Article  Google Scholar 

  16. Qi, Y. et al. Piezoelectric ribbons printed onto rubber for flexible energy conversion. Nano Lett. 10, 524–528 (2010).

    Article  ADS  Google Scholar 

  17. Lipomi, D. J., Tee, B. C. K., Vosgueritchian, M. & Bao, Z. Stretchable organic solar cells. Adv. Mater. 23, 1771–1775 (2011).

    Article  Google Scholar 

  18. Koo, W. H. et al. Light extraction from organic light-emitting diodes enhanced by spontaneously formed buckles. Nature Photon. 4, 222–226 (2010).

    Article  ADS  Google Scholar 

  19. Brau, F. et al. Multiple-length-scale elastic instability mimics parametric resonance of nonlinear oscillators. Nature Phys. 7, 56–60 (2011).

    Article  ADS  Google Scholar 

  20. Schnell, M. et al. Nanofocusing of mid-infrared energy with tapered transmission lines. Nature Photon. 5, 283–287 (2011).

    Article  ADS  Google Scholar 

  21. Verhagen, E., Spasenovicacute, M., Polman, A. & Kuipers, L. Nanowire plasmon excitation by adiabatic mode transformation. Phys. Rev. Lett. 102, 203904 (2009).

    Article  ADS  Google Scholar 

  22. van Dillen, T., Polman, A., van Kats, C. M. & van Blaaderen, A. Ion beam-induced anisotropic plastic deformation at 300 keV. Appl. Phys. Lett. 83, 4315–4317 (2003).

    Article  ADS  Google Scholar 

  23. Kim, J. B. et al. Small-molecule thiophene–C60 dyads as compatibilizers in inverted polymer solar cells. Chem. Mater. 22, 5762–5773 (2010).

    Article  Google Scholar 

  24. Guan, Z.-L. et al. Direct determination of the electronic structure of the poly(3-hexylthiophene):phenyl-[6,6]-C61 butyric acid methyl ester blend. Org. Electron. 11, 1779–1785 (2010).

    Article  Google Scholar 

  25. Wang, H. et al. Device characteristics of bulk-heterojunction polymer solar cells are independent of interfacial segregation of active layers. Chem. Mater. 23, 2020–2023 (2011).

    Article  Google Scholar 

  26. Lee, J. K. et al. Efficacy of TiOx optical spacer in bulk-heterojunction solar cells processed with 1,8-octanedithiol. Appl. Phys. Lett. 92, 243308 (2008).

    Article  ADS  Google Scholar 

  27. Blom, P. W. M., Mihailetchi, V. D., Koster, L. J. A. & Markov, D. E. Device physics of polymer:fullerene bulk heterojunction solar cells. Adv. Mater. 19, 1551–1566 (2007).

    Article  Google Scholar 

  28. Vandewal, K. et al. The relation between open-circuit voltage and the onset of photocurrent generation by charge-transfer absorption in polymer:fullerene bulk heterojunction solar cells. Adv. Funct. Mater. 18, 2064–2070 (2008).

    Article  Google Scholar 

  29. Street, R. A., Song, K. W., Northrup, J. E. & Cowan, S. Photoconductivity measurements of the electronic structure of organic solar cells. Phys. Rev. B 83, 165207 (2011).

    Article  ADS  Google Scholar 

  30. Atwater, H. A. & Polman, A. Plasmonics for improved photovoltaic devices. Nature Mater. 9, 205–213 (2010).

    Article  ADS  Google Scholar 

  31. Ferry, V. E., Sweatlock, L. A., Pacifici, D. & Atwater, H. A. Plasmonic nanostructure design for efficient light coupling into solar cells. Nano Lett. 8, 4391–4397 (2008).

    Article  ADS  Google Scholar 

  32. Ferry, V. E. et al. Improved red-response in thin film a-Si:H solar cells with soft-imprinted plasmonic back reflectors. Appl. Phys. Lett. 95, 183503 (2009).

    Article  ADS  Google Scholar 

  33. Baca, A. J. et al. Semiconductor wires and ribbons for high-performance flexible electronics. Angew. Chem. Int. Ed. 47, 5524–5542 (2008).

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by a grant from the Photovoltaics Program at ONR (N00014-11-10328) to J.B.K and Y.-L.L. J.B.K., Y.-L.L., P.K. and H.A.S. also acknowledge funding through the Princeton Center for Complex Materials, an NSF-sponsored MRSEC (DMR-0819860). N.C.P. and J.W.F. acknowledge the support of the Air Force Office of Scientific Research (US-AFOSR). S.J.O. and C.R.K. acknowledge the support of the NSF CBET programme (CBET-0854226). The authors would also like to thank B. Rand of IMEC for extensive discussions.

Author information

Authors and Affiliations

Authors

Contributions

J.B.K. fabricated and tested the polymer solar cells on rigid and flexible substrates. P.K. constructed the surfaces with wrinkles and folds. N.C.P. performed optical simulations and theory. J.B.K. and S.O. carried out local photocurrent mapping. All authors were involved in extensive discussions and data analyses. J.B.K. and Y.-L.L. wrote the manuscript with input from the other authors.

Corresponding author

Correspondence to Yueh-Lin Loo.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 1519 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kim, J., Kim, P., Pégard, N. et al. Wrinkles and deep folds as photonic structures in photovoltaics. Nature Photon 6, 327–332 (2012). https://doi.org/10.1038/nphoton.2012.70

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nphoton.2012.70

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing