Tin (Sn)-based halide perovskites have potential as next-generation semiconducting materials for optoelectronic devices - due to good charge-transport characteristics, and facile processability[1],[2]. Two-dimensional (2D) Ruddlesden-Popper perovskites (RPPs) show a layered structure of [SnX6]4- octahedra and insulating organic spacers, giving effective barriers against oxygen and moisture. However, due to the bulky organic layer, efficient charge transport is hampered across the layers. In this work, we utilized template-assisted crystallization method for enhanced perovskite crystallinity, inducing perovskite to form periodic nanograting grooves during crystallization process. The nanograting grooves lower the carrier effective mass by inducing near-surface compressive lattice strain. The resulting PEA2SnI4 TFTs achieved high mobility exceeding 24 cm2V-1s-1, on/off current ratios higher than 107, a subthreshold swing of 0.95 V dec-1, and great environmental and operational stability.
[1] Lin, R., Xu, J., Wei, M. et al., Nature, 603, 73-78 (2022)
[2] Park, H., Lee, C.B., Lee, J. et al., Nat Electron, 8, 934–948 (2025)