Lead-Free Bismuth-Based Organic-Inorganic Hybrid Material (2-4py)BiI4 Solar Cell with High Damp-Heat Stability

Authors：Zhu, Yin; Hu, Xinru; Zheng, Guoyuan; Wei, Xiaopeng; He, Jian; Wang, Jilin^*; Lin, Bencai; Yao, Disheng; Tian, Nan; Mo, Shuyi; Long, Fei^*

Source：Journal of Electronic Materials, 2023, 52(8): 5554-5563.

DOI：10.1007/s11664-023-10467-x

• Lead-free
• organic-inorganic hybrid
• solar cell
• bismuth (III) based hybrid compound

The high stability and low toxicity of bismuth-based perovskite materials can overcome current issues of lead-based perovskite solar cells (PSCs). In this study, a stable 2-amino-4-picoline (2-4py)-based bismuth perovskite material [(C6H9N2)BiI4] was developed, which has a low band gap and high stability. A one-step solution spin-coating method was used to prepare (C6H9N2)BiI4 film as the light-absorbing layer. The electron transport layers were composed of compact TiO2 (c-TiO2) and mesoporous TiO2 (mes-TiO2). Measurements by UV-vis and time-resolved photoluminescence showed that the band gap of (C6H9N2)BiI4 film was 2.0 eV and the fluorescence lifetime was 21.58 ns. The materials were assembled into a device, and comparative experimental results showed that the highest power conversion efficiency of fluorine-doped SnO2 (FTO)/c-TiO2 + mes-TiO2/(C6H9N2)BiI4/Spiro-OMeTAD/Au was 0.0328%. Although the efficiency of the current device was low, the (C6H9N2)BiI4 material exhibited excellent stability in hot and wet conditions. This indicates that (C6H9N2)BiI4 has potential for use in highly stable solar cells.

• Institution
  常州大学; 桂林理工大学