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.

  • Article
  • Published:

Electro-optics of perovskite solar cells

Nature Photonics volume 9, pages 106–112 (2015)Cite this article

Subjects

Abstract

Organohalide-perovskite solar cells have emerged as a leading next-generation photovoltaic technology. However, despite surging efficiencies, many questions remain unanswered regarding the mechanisms of operation. Here we report a detailed study of the electro-optics of efficient CH3NH3PbI3-perovskite-only planar devices. We report the dielectric constants over a large frequency range. Importantly, we found the real part of the static dielectric constant to be ∼70, from which we estimate the exciton-binding energy to be of order 2 meV, which strongly indicates a non-excitonic mechanism. Also, Jonscher's Law behaviour was consistent with the perovskite having ionic character. Accurate knowledge of the cell's optical constants allowed improved modelling and design, and using this information we fabricated an optimized device with an efficiency of 16.5%. The optimized devices have ∼100% spectrally flat internal quantum efficiencies and minimal bimolecular recombination. These findings establish systematic design rules to achieve silicon-like efficiencies in simple perovskite solar cells.

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

Access options

Buy this article

  • Purchase on SpringerLink
  • Instant access to full article PDF
Buy now

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

Figure 1: Materials and their properties used in the CH3NH3PbI3 non-oxide perovskite solar cells.
Figure 2: Optical and dielectric properties of the CH3NH3PbI3 perovskite.
Figure 3: Electro-optical modelling of perovskite solar cells.
Figure 4: Solar-cell performance of the ‘hero’ CH3NH3PbI3 perovskite.

Similar content being viewed by others

References

  1. Service, R. F. Perovskite solar cells keep on surging. Science 344, 458–458 (2014).

    Article  ADS  Google Scholar 

  2. Burn, P. L. & Meredith, P. The rise of the perovskites: the future of low cost solar photovoltaics. NPG Asia Mater. 6, e79 (2014).

    Article  Google Scholar 

  3. Kojima, A., Teshima, K., Shirai, Y. & Miyasaka, T. Organometal halide perovskites as visible-light sensitizers for photovoltaic cells. J. Am. Chem. Soc. 131, 6050–6051 (2009).

    Article  Google Scholar 

  4. Jeon, N. J. et al. o-Methoxy substituents in spiro-OMeTAD for efficient inorganic–organic hybrid perovskite solar cells. J. Am. Chem. Soc. 136, 7837–7840 (2014).

    Article  Google Scholar 

  5. Zhou, H. et al. Interface engineering of highly efficient perovskite solar cells. Science 345, 542–546 (2014).

    Article  ADS  Google Scholar 

  6. Burschka, J. et al. Sequential deposition as a route to high-performance perovskite-sensitized solar cells. Nature 499, 316–319 (2013).

    Article  ADS  Google Scholar 

  7. Liu, M. Z., Johnston, M. B. & Snaith, H. J. Efficient planar heterojunction perovskite solar cells by vapour deposition. Nature 501, 395–398 (2013).

    Article  ADS  Google Scholar 

  8. Docampo, P., Ball, J. M., Darwich, M., Eperon, G. E. & Snaith, H. J. Efficient organometal trihalide perovskite planar-heterojunction solar cells on flexible polymer substrates. Nature Commun. 4, 2761 (2013).

    Article  ADS  Google Scholar 

  9. Etgar, L. et al. Mesoscopic CH3NH3PbI3/TiO2 heterojunction solar cells. J. Am. Chem. Soc. 134, 17396–17399 (2012).

    Article  Google Scholar 

  10. Wojciechowski, K., Saliba, M., Leijtens, T., Abate, A. & Snaith, H. Sub 150 °C processed meso-superstructured perovskite solar cells with enhanced efficiency. Energy Environ. Sci. 7, 1142–1147 (2014).

    Article  Google Scholar 

  11. Malinkiewicz, O. et al. Perovskite solar cells employing organic charge-transport layers. Nature Photon. 8, 128–132 (2014).

    Article  ADS  Google Scholar 

  12. D'Innocenzo, V. et al. Excitons versus free charges in organo-lead tri-halide perovskites. Nature Commun. 5, 3586 (2014).

    Article  ADS  Google Scholar 

  13. Marchioro, A. et al. Unravelling the mechanism of photoinduced charge transfer processes in lead iodide perovskite solar cells. Nature Photon. 8, 250–255 (2014).

    Article  ADS  Google Scholar 

  14. Lee, M. M., Teuscher, J., Miyasaka, T., Murakami, T. N. & Snaith H. J. Efficient hybrid solar cells based on meso-superstructured organometal halide perovskites. Science 338, 643–647 (2012).

    Article  ADS  Google Scholar 

  15. Stranks, S. D. et al. Electron-hole diffusion lengths exceeding 1 micrometer in an organometal trihalide perovskite absorber. Science 342, 341–344 (2013).

    Article  ADS  Google Scholar 

  16. Qin, P. et al. Inorganic hole conductor-based lead halide perovskite solar cells with 12.4% conversion efficiency. Nature Commun. 5, 3834 (2014).

    Article  ADS  Google Scholar 

  17. Hirasawa, M., Ishihara, T., Goto, T., Uchida, K. & Miura, N. Magnetoabsorption of the lowest exciton in perovskite-type compound (CH3NH3)PbI3 . Physica B 201, 427–430 (1994).

    Article  ADS  Google Scholar 

  18. Hirasawa, M., Ishihara, T. & Goto, T. Exciton features in 0-dimensional, 2-dimensional, and 3-dimensional networks of [PbI6]4− octahedra. J. Phys. Soc. Jpn 63, 3870–3879 (1994).

    Article  ADS  Google Scholar 

  19. Muljarov, E. A., Tikhodeev, S. G., Gippius, N. A. & Ishihara, T. Excitons in self-organized semiconductor/insulator superlattices: PbI-based perovskite compounds. Phys. Rev. B 51, 14370–14378 (1995).

    Article  ADS  Google Scholar 

  20. Tanaka, K. et al. Comparative study on the excitons in lead–halide-based perovskite-type crystals CH3NH3PbBr3 and CH3NH3PbI3 . Solid State Commun. 127, 619–623 (2003).

    Article  ADS  Google Scholar 

  21. Pankove, J. I. Optical Progresses in Semiconductors (Dover Publications, 2010).

    Google Scholar 

  22. Roessler, D. M. Kramers–Kronig analysis of non-normal incidence reflection. Br. J. Appl. Phys. 16, 1359–1366 (1965).

    Article  ADS  Google Scholar 

  23. Xing, G. et al. Low-temperature solution-processed wavelength-tunable perovskites for lasing. Nature Mater. 13, 476–480 (2014).

    Article  ADS  Google Scholar 

  24. Armin, A. et al. Doping-induced screening of the built-in-field in organic solar cells: effect on charge transport and recombination. Adv. Energy Mater. 3, 321–327 (2013).

    Article  Google Scholar 

  25. Brivio, F., Butler, K. T., Walsh, A. & van Schilfgaarde, M. Relativistic quasiparticle self-consistent electronic structure of hybrid halide perovskite photovoltaic absorbers. Phys. Rev. B 89, 155204 (2014).

    Article  ADS  Google Scholar 

  26. Onoda-Yamamuro, N., Matsuo, T. & Suga, H. Dielectric study of CH3NH3PbX3 (X = Cl, Br, I). J. Phys. Chem. Solids 53, 935–939 (1992).

    Article  ADS  Google Scholar 

  27. Jonscher, A. K. Analysis of the alternating current properties of ionic conductors. J. Mater. Sci. 13, 553–562 (1978).

    Article  ADS  Google Scholar 

  28. Frost, J. M., Butler, K. T. & Walsh, A. Molecular ferroelectric contributions to anomalous hysteresis in hybrid perovskite solar cells. APL Mater. 2, 081506 (2014).

    Article  ADS  Google Scholar 

  29. Philipp, H. R. & Ehrenreich, H. Optical properties of semiconductors. Phys. Rev. 129, 1550–1560 (1963).

    Article  ADS  Google Scholar 

  30. Huang, L. Y. & Lambrecht, W. R. Electronic band structure, phonons, and exciton binding energies of halide perovskites CsSnCl3, CsSnBr3, and CsSnI3 . Phys. Rev. B 88, 165203 (2013).

    Article  ADS  Google Scholar 

  31. Madelung, O. Introduction to Solid-State Theory Vol. 2 (Springer, 1996).

    Google Scholar 

  32. Taguchi, S., Goto, T., Takeda, M. & Kido, G. Magneto-optical effects of the Wannier exciton in a biaxial ZnP crystal. I. J. Phys. Soc. Jpn 57, 3256–3261 (1988).

    Article  ADS  Google Scholar 

  33. Frost, J. M. et al. Atomistic origins of high-performance in hybrid halide perovskite solar cells. Nano Lett. 14, 2584–2590 (2014).

    Article  ADS  Google Scholar 

  34. Pelant, I. & Valenta, J. Luminescence Spectroscopy of Semiconductors (Oxford Univ. Press, 2012).

    Book  Google Scholar 

  35. Burkhard, G. F., Hoke, E. T. & McGehee, M. D. Accounting for interference, scattering, and electrode absorption to make accurate internal quantum efficiency measurements in organic and other thin solar cells. Adv. Mater. 22, 3293–3297 (2010).

    Article  Google Scholar 

  36. Armin, A. et al. Quantum efficiency of organic solar cells: electro-optical cavity considerations. ACS Photon. 1, 173–181 (2014).

    Article  Google Scholar 

  37. Snaith, H. J. et al. Anomalous hysteresis in perovskite solar cells. J. Phys. Chem. Lett. 5, 1511–1515 (2014).

    Article  Google Scholar 

  38. Wang, Q., et al. Large fill-factor bilayer iodine perovskite solar cells fabricated by a low-temperature solution-process. Energy Environ. Sci. 7, 2359–2365 (2014).

    Article  Google Scholar 

  39. Malinkiewicz, O. et al. Metal-oxide-free methylammonium lead iodide perovskite-based solar cells: the influence of organic charge transport layers. Adv. Energy Mater. 4, 1400345 (2014).

    Article  Google Scholar 

  40. Pettersson, L. A. A., Roman, L. S. & Inganäs, O. Modeling photocurrent action spectra of photovoltaic devices based on organic thin films. J. Appl. Phys. 86, 487–496 (1999).

    Article  ADS  Google Scholar 

  41. Grundmann, M. The Physics of Semiconductors (Springer, 2006).

    Google Scholar 

  42. Klingshirn, C. F. Semiconductor Optics Vol. 3 (Springer, 2007).

    Book  Google Scholar 

  43. Mosconi, E., Amat, A., Nazeeruddin, M. K., Grätzel, M. & De Angelis, F. First-principles modeling of mixed halide organometal perovskites for photovoltaic applications. J. Phys. Chem. C 117, 13902–13913 (2013).

    Article  Google Scholar 

  44. Roth, L. M., Lax, B. & Zwerdling, S. Theory of optical magneto-absorption effects in semiconductors. Phys. Rev. 114, 90–103 (1959).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

P.L.B. is a University of Queensland (UQ) Vice Chancellor's Senior Research Fellow and P.M. is an Australian Research Council Discovery Outstanding Researcher Award Fellow. A.A. was supported by a UQ International Postgraduate Award. Q.L. is supported by an International Postgraduate Research Scholarship and R.C.R.N. was supported by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Future Manufacturing Flagship: Flexible Transparent Electrodes for Plastic Electronics Cluster, which includes The University of Queensland, University of Technology, Sydney, and Flinders University. We acknowledge funding from the University of Queensland (Strategic Initiative – Centre for Organic Photonics & Electronics). This work was performed in part at the Queensland node of the Australian National Fabrication Facility, a company established under the National Collaborative Research Infrastructure Strategy to provide nano- and microfabrication facilities for Australia's researchers. This Program has also been supported by the Australian Government through the Australian Renewable Energy Agency, Australian Centre for Advanced Photovoltaics. Responsibility for the views, information or advice expressed herein is not accepted by the Australian Government. We thank the Institute for Materials Research and Engineering (Singapore) for supplying the DPP-DTT and S. Watkins at CSIRO for photoelectron spectroscopy in air measurements.

Author information

Authors and Affiliations

  1. Centre for Organic Photonics & Electronics, School of Chemistry and Molecular Biosciences and School of Mathematics and Physics, The University of Queensland, St Lucia Campus, Brisbane, 4072, Australia

    Qianqian Lin, Ardalan Armin, Ravi Chandra Raju Nagiri, Paul L. Burn & Paul Meredith

Authors
  1. Qianqian Lin
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Ardalan Armin
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Ravi Chandra Raju Nagiri
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Paul L. Burn
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Paul Meredith
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

Q.L. synthesized the MAI, prepared perovskite films and performed the basic characterization. Q.L. fabricated the solar-cell devices and Q.L. and A.A. tested them. Q.L., A.A., P.M. and P.L.B. designed the devices and experiments. R.C.R.N. and P.M. performed the spectroscopic ellipsometry and reflectometry and R.C.R.N., P.M. and A.A. fitted the data. A.A. and P.M. carried out the dielectric constant/binding energy analysis. All the authors contributed in writing the manuscript.

Corresponding authors

Correspondence to Paul L. Burn or Paul Meredith.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lin, Q., Armin, A., Nagiri, R. et al. Electro-optics of perovskite solar cells. Nature Photon 9, 106–112 (2015). https://doi.org/10.1038/nphoton.2014.284

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nphoton.2014.284

This article is cited by

Search

Advanced 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