Highly Air-Stable Tin-Based Perovskite Solar Cells through Grain-Surface Protection by Gallic Acid

Tianyue Wang, Qidong Tai, Xuyun Guo, Jiupeng Cao, Chun Ki Liu, Naixiang Wang, Dong Shen, Ye Zhu, Chun Sing Lee, Feng Yan

Research output: Journal article publicationJournal articleAcademic researchpeer-review

52 Citations (Scopus)


Maintaining the stability of tin halide perovskites is a major challenge in developing lead-free perovskite solar cells (PSCs). Adding extra SnX2 (X = F, Cl, or Br) in the precursor solution to inhibit Sn2+ oxidation is an essential strategy to improve device efficiency and stability. However, SnX2 on the surface of perovskite grains tends to prohibit charge transfer across perovskite films. Here, we report a coadditive engineering approach by introducing antioxidant gallic acid (GA) together with SnCl2 to improve the performance of tin-based PSCs. The SnCl2-GA complex can not only protect the perovskite grains but also more effectively conduct electrons across it, leading to highly stable and efficient PSCs. The unencapsulated devices can maintain ∼80% of their initial efficiency after 1000 h of storage in ambient air with a relative humidity of 20%, which is the best air stability achieved in tin-based PSCs to date.

Original languageEnglish
Pages (from-to)1741-1749
Number of pages9
JournalACS Energy Letters
Issue number6
Publication statusPublished - 12 Jun 2020

ASJC Scopus subject areas

  • Chemistry (miscellaneous)
  • Renewable Energy, Sustainability and the Environment
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Materials Chemistry

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