Article

In situ observation of heat-induced degradation of perovskite solar cells

  • Nature Energy 1, Article number: 15012 (2016)
  • doi:10.1038/nenergy.2015.12
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Abstract

The lack of thermal stability of perovskite solar cells is hindering the progress of this technology towards adoption in the consumer market. Different pathways of thermal degradation are activated at different temperatures in these complex nanostructured hybrid composites. Thus, it is essential to explore the thermal response of the mesosuperstructured composite device to engineer materials and operating protocols. Here we produce devices according to four well-established recipes, and characterize their photovoltaic performance as they are heated within the operational range. The devices are analysed using transmission electron microscopy as they are further heated in situ, to monitor changes in morphology and chemical composition. We identify mechanisms for structural and chemical changes, such as iodine and lead migration, which appear to be correlated to the synthesis conditions. In particular, we identify a correlation between exposure of the perovskite layer to air during processing and elemental diffusion during thermal treatment.

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Acknowledgements

G.D., S.C. and C.D. acknowledge funding from ERC under grant number 259619 PHOTO EM. C.D. acknowledges financial support from the EU under grant number 312483 ESTEEM2. F.M., L.C. and A.D.C. acknowledge funding from ‘Polo Solare Organico’ Regione Lazio, the ‘DSSCX’ MIUR-PRIN2010 and FP7 ITN ‘Destiny’. G.D. and S.C. thank F. de la Peña and P. Burdet for assistance with PCA analysis.

Author information

Affiliations

  1. Department of Materials Science & Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK

    • G. Divitini
    • , S. Cacovich
    •  & C. Ducati
  2. C.H.O.S.E. (Centre for Hybrid and Organic Solar Energy), Department of Electronic Engineering, University of Rome “Tor Vergata”, via del Politecnico 1, Rome 00133, Italy

    • F. Matteocci
    • , L. Cinà
    •  & A. Di Carlo

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Contributions

G.D., F.M., A.D.C. and C.D. conceived and designed the experiment. F.M. produced the devices. F.M. and L.C. carried out photovoltaic characterization. G.D. and S.C. carried out sample preparation, electron microscopy and data analysis. All authors contributed to the discussion of the results and to the writing of the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to G. Divitini.

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    Supplementary Figures 1-9

Videos

  1. 1.

    Supplementary Video 1

    Sample A: montage of STEM-HAADF images upon heating.

  2. 2.

    Supplementary Video 2

    Sample B: montage of STEM-HAADF images upon heating.

  3. 3.

    Supplementary Video 3

    Sample C: Montage of STEM-HAADF images upon heating.

  4. 4.

    Supplementary Video 4

    Sample D: montage of STEM-HAADF images upon heating.