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A fluorene-terminated hole-transporting material for highly efficient and stable perovskite solar cells

Nature Energyvolume 3pages682689 (2018) | Download Citation

Abstract

Perovskite solar cells (PSCs) require both high efficiency and good long-term stability if they are to be commercialized. It is crucial to finely optimize the energy level matching between the perovskites and hole-transporting materials to achieve better performance. Here, we synthesize a fluorene-terminated hole-transporting material with a fine-tuned energy level and a high glass transition temperature to ensure highly efficient and thermally stable PSCs. We use this material to fabricate photovoltaic devices with 23.2% efficiency (under reverse scanning) with a steady-state efficiency of 22.85% for small-area (~0.094 cm2) cells and 21.7% efficiency (under reverse scanning) for large-area (~1 cm2) cells. We also achieve certified efficiencies of 22.6% (small-area cells, ~0.094 cm2) and 20.9% (large-area, ~1 cm2). The resultant device shows better thermal stability than the device with spiro-OMeTAD, maintaining almost 95% of its initial performance for more than 500 h after thermal annealing at 60 °C.

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Acknowledgements

This work was supported by a grant from the Korea Research Institute of Chemical Technology (KRICT), Republic of Korea (KK1802-A01), the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade Industry & Energy (MOTIE) of the Republic of Korea (No. 20163010012470), and by a grant from the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (MSIP) of Korea (NRF-2016M3A6A7945503). This research was also supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1A6A3A04058164).

Author information

Author notes

  1. These authors contributed equally: Nam Joong Jeon, Hyejin Na, Eui Hyuk Jung.

Affiliations

  1. Division of Advanced Materials, Korea Research Institute of Chemical Technology (KRICT), Daejeon, South Korea

    • Nam Joong Jeon
    • , Hyejin Na
    • , Eui Hyuk Jung
    • , Tae-Youl Yang
    • , Yong Guk Lee
    • , Geunjin Kim
    • , Sang Il Seok
    • , Jaemin Lee
    •  & Jangwon Seo
  2. Department of Energy Science, Sungkyunkwan University, Suwon, South Korea

    • Hee-Won Shin
  3. School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea

    • Sang Il Seok

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Contributions

J.S. and J.L. conceived and supervised the project. N.J.J., E.H.J., S.I.S., J.S. and J.L. wrote the paper. N.J.J. and E.H.J. fabricated and characterized the perovskite solar cells. N.J.J., E.H.J. and J.S. achieved the certified performance of devices at Newport Corporation. H.N. synthesized the relevant materials. H.N. and Y.G.L. performed analysis of the intrinsic properties of the materials via DFT calculation, ultraviolet–visible absorption, CV, TGA, DSC and SCLC measurements. N.J.J. and E.H.J. carried out SEM measurements. T.Y.Y. and H.W.S. analysed charge recombination lifetimes via transient photovoltage measurements as a function of the bias light intensity. G.K. performed TRPL measurements. All authors discussed the results.

Competing interests

The authors declare no competing interests.

Corresponding authors

Correspondence to Jaemin Lee or Jangwon Seo.

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DOI

https://doi.org/10.1038/s41560-018-0200-6