Circularly Polarized Luminescence in Achiral Tin-Based Perovskites via Structural Isomer-Driven Coordination Interaction.

A chiral bidentate ligand, ()-(-)-1-amino-2-propanol (denoted as R) or ()-(-)-2-amino-1-propanol (denoted as R), was used to modify achiral 2D tin-based perovskite HDASnBr (HDA: 1,6-hexamethylenediamine) to form R-HDASnBr or R-HDASnBr by an acid precipitation method. R-HDASnBr exhibits a near-unity photoluminescence quantum yield (PLQY) and strong yellow circularly polarized luminescence (CPL) with a luminescence asymmetry g-factor (||) of 8.3 × 10, while R-HDASnBr shows a PLQY of 95% and || of 3.2 × 10. Both exhibit strong CPL activities, attributed to the significant centro-asymmetric distortion induced by the interaction between the chiral ligand and the inorganic lattice of 2D perovskites. The || of RHDASnBr is 2.6× that of R-HDASnBr, resulting from the direct coordination of the hydroxyl group attached to the chiral carbons in R with the [SnBr] inorganic framework, which induces a higher degree of distortion than the amino group in R. Furthermore, we explored the potential of R-HDASnBr as a chiral inducer and a CPL source to facilitate asymmetric polymerization. This work offers a simple strategy to introduce chirality to achiral perovskites.