DOI: https://doi.org/10.29363/nanoge.sus-mhp.2022.009
Publication date: 15th November 2022
Hybrid tin (Sn) perovskite has been regarded as the most promising alternative material for lead (Pb) based perovskite, achieving a PCE of over 14% in 2021.[1] Antisolvents treatment has been widely used in the preparation of different Sn perovskite to improve the film quality and device performances.[2] However, the mechanism behind the antisolvent treatment for Sn perovskite is still unclear.
In this work we studied the effects of different antisolvents on 2D/3D Sn perovskite (PEA0.2FA0.8SnI3) perovskite solar cells. Diisopropyl ether (DIE), Diethyl ether (DE) toluene and chlorobenzene (CB) are applied as antisolvent during the film fabrication. Among these antisolvents the perovskite film treated by DIE revealed the highest crystallinity, achieving a PCE of 10.2%, better than DE, toluene and CB sequentially. We found that the origin of the improvement of PCE treated by DIE is correlated to the better distribution and higher fractions of the 2D phase inside the film, leading to better film quality and higher open circuit voltage. Besides, the higher amount of 2D phase can also enhance the stability of Sn perovskite under ambient atmosphere. Our findings not only show the importance of the 2D phase in 2D/3D Sn perovskite but also suggest that the compositions of the mixed cation perovskite could be influenced by different antisolvents.
We would like to thank the financial support from EPSRC (grants EP/R020574/1 and EP/R023581/1) and the Royal Commission for the Exhibition of 1851 for their financial support through a Research Fellowship.