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Coadditive Engineering with 5-Ammonium Valeric Acid Iodide for Efficient and Stable Sn Perovskite Solar Cells

  • Md. Emrul Kayesh
    Md. Emrul Kayesh
    Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047, Japan
    Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
    More by Md. Emrul Kayesh
    • , 
  • Kiyoto Matsuishi*
    Kiyoto Matsuishi
    Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
    *E-mail: [email protected]
    More by Kiyoto Matsuishi
    • , 
  • Ryuji Kaneko
    Ryuji Kaneko
    Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047, Japan
    More by Ryuji Kaneko
    • , 
  • Said Kazaoui
    Said Kazaoui
    Research Center for Photovoltaics (RCPV), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
    More by Said Kazaoui
    Orcidhttp://orcid.org/0000-0002-2295-5874
    • , 
  • Jae-Joon Lee
    Jae-Joon Lee
    Department of Energy & Materials Engineering & Research Center for Photoenergy Harvesting and Conversion Technology, Dongguk University, Seoul 04620, Republic of Korea
    More by Jae-Joon Lee
    • , 
  • Takeshi Noda
    Takeshi Noda
    Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047, Japan
    More by Takeshi Noda
    • , and 
  • Ashraful Islam*
    Ashraful Islam
    Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047, Japan
    *E-mail: [email protected]
    More by Ashraful Islam
    Orcidhttp://orcid.org/0000-0002-1633-1432
Cite this: ACS Energy Lett. 2019, 4, 1, 278–284
Publication Date (Web):December 18, 2018
https://doi.org/10.1021/acsenergylett.8b02216
Copyright © 2018 American Chemical Society
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Abstract

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Sn-based perovskite solar cells (PSCs) featuring high performance and long-term stability are very challenging because Sn2+ is relatively prone to oxidation. Here, we have performed coadditive engineering with 5-ammonium valeric acid iodide (5-AVAI) for FASnI3-based perovskite films. From the morphological, structural, and elemental analyses, we observed that 5-AVAI affects the crystal growth of perovskites through its hydrogen bond with I– of the SnI64– octahedral. As a result, pinhole-free homogeneous and stable Sn-based perovskite films form over a large area with lower Sn4+ content. This made us able to enhance the power conversion efficiency (PCE) for Sn-based PSCs up to 7% in a 0.25 cm2 aperture area. Most importantly, the 5-AVAI added PSCs showed a record stability and maintained their initial PCE under 1 sun continuous illumination at maximum power point tracking for 100 h.

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This article is cited by 46 publications.

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