Review Article | Published:

Materials interface engineering for solution-processed photovoltaics

Nature volume 488, pages 304312 (16 August 2012) | Download Citation

Abstract

Advances in solar photovoltaics are urgently needed to increase the performance and reduce the cost of harvesting solar power. Solution-processed photovoltaics are cost-effective to manufacture and offer the potential for physical flexibility. Rapid progress in their development has increased their solar-power conversion efficiencies. The nanometre (electron) and micrometre (photon) scale interfaces between the crystalline domains that make up solution-processed solar cells are crucial for efficient charge transport. These interfaces include large surface area junctions between photoelectron donors and acceptors, the intralayer grain boundaries within the absorber, and the interfaces between photoactive layers and the top and bottom contacts. Controlling the collection and minimizing the trapping of charge carriers at these boundaries is crucial to efficiency.

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Acknowledgements

E.H.S acknowledges that this Review is based, in part, on work supported by an award (no. KUS-11-009-21) made by King Abdullah University of Science and Technology (KAUST), by the Ontario Research Fund Research Excellence Program and by the Natural Sciences and Engineering Research Council (NSERC) of Canada. E.H.S acknowledges the contribution of I. Kramer, S. Thon and O. Voznyy to the figures and text. M.G. acknowledges that this Review is based, in part, on work supported by the Stanford University Center of Advanced Molecular Photovoltaics (CAMP) under an award (no. KUSC1-015-21) made by KAUST and by the European Research Council (ERC) under the Advanced Research Grant No. 247404 (Mesolight project).

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Affiliations

  1. Institute of Photonics and Interfaces, Swiss Federal Institute of Technology, CH-1015 Lausanne, Switzerland.

    • Michael Graetzel
  2. Molecular Materials and Nanosystems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.

    • René A. J. Janssen
  3. IBM TJ Watson Research Center, Yorktown Heights, New York 10598, USA.

    • David B. Mitzi
  4. Department of Electrical and Computer Engineering, University of Toronto, Toronto, M5S 3G4, Canada.

    • Edward H. Sargent

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The authors declare no competing financial interests.

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Correspondence to Edward H. Sargent.

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https://doi.org/10.1038/nature11476

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