1. A green solvent enables precursor phase engineering of stable formamidinium lead triiodide perovskite solar cells
- Author
-
Benjamin M. Gallant, Philippe Holzhey, Joel A. Smith, Saqlain Choudhary, Karim A. Elmestekawy, Pietro Caprioglio, Igal Levine, Alexandra A. Sheader, Esther Y-H. Hung, Fengning Yang, Daniel T. W. Toolan, Rachel C. Kilbride, Karl-Augustin Zaininger, James M. Ball, M. Greyson Christoforo, Nakita K. Noel, Laura M. Herz, Dominik J. Kubicki, and Henry J. Snaith
- Subjects
Science - Abstract
Abstract Perovskite solar cells (PSCs) offer an efficient, inexpensive alternative to current photovoltaic technologies, with the potential for manufacture via high-throughput coating methods. However, challenges for commercial-scale solution-processing of metal-halide perovskites include the use of harmful solvents, the expense of maintaining controlled atmospheric conditions, and the inherent instabilities of PSCs under operation. Here, we address these challenges by introducing a high volatility, low toxicity, biorenewable solvent system to fabricate a range of 2D perovskites, which we use as highly effective precursor phases for subsequent transformation to α-formamidinium lead triiodide (α-FAPbI3), fully processed under ambient conditions. PSCs utilising our α-FAPbI3 reproducibly show remarkable stability under illumination and elevated temperature (ISOS-L-2) and “damp heat” (ISOS-D-3) stressing, surpassing other state-of-the-art perovskite compositions. We determine that this enhancement is a consequence of the 2D precursor phase crystallisation route, which simultaneously avoids retention of residual low-volatility solvents (such as DMF and DMSO) and reduces the rate of degradation of FA+ in the material. Our findings highlight both the critical role of the initial crystallisation process in determining the operational stability of perovskite materials, and that neat FA+-based perovskites can be competitively stable despite the inherent metastability of the α-phase.
- Published
- 2024
- Full Text
- View/download PDF