Structure-Property Relationships in Triple-Cation Sn-Based Perovskites for High-Mobility Field-Effect Transistors

Solution-processable hybrid organic-inorganic halide perovskites have emerged as a transformative class of materials for optoelectronic devices such as solar cells, LEDs and photodetectors. Their exceptional charge transport properties, combined with low-temperature processability, make perovskite semiconductors highly appealing also for flexible electronics. However, operational challenges such as ion migration, interface instabilities, and device integration impede their scalability and long-term performance. Recently, Sn-based perovskites have demonstrated potential to achieve high-performance field-effect transistors (FETs) with suppressed ion-migration^[1]. Remarkably, mixed 2D-3D Sn-based compositions have achieved record-breaking charge carrier mobility (>50 cm²/Vs) in solution-processed FETs. ^[2]
Here, we explore the charge transport properties of solution-processed triple-cation Sn-based perovskite (Cs_0.1FA_0.9)_xPEA_1-xSnI₃, focusing on the influence of organic cations and interface optimization.^[3] Advanced FET and gated Hall measurements allow reliable extraction of charge carrier mobility and contact resistance. We establish a correlation between temperature-dependent mobility, GIWAXS and photoluminescence measurements. Furthermore, high-resolution TEM uncovers the critical impact of crystallinity and device interfaces to achieve efficient long-range polaron transport in perovskite FETs.

[1] Senanayak, S. P., et al, Nat. Mater. 22, 216–224 (2023).
[2] Zhu, H., et al. Nat Electron 6, 650–657 (2023).
[3] Pecorario S., Sirringhaus H., et al., in preparation.