Chiral 2D Perovskites with High Degree of Circularly Polarized Photoluminescence

Chiral materials are of particular interest and have a wide range of potential applications in life science, material science, spintronic and optoelectronic devices. Two-dimensional (2D) hybrid organic-inorganic lead halide perovskites have attracted increasing attention. Incorporating the chiral organic ligands into the layered lead-iodide frameworks would introduce strong chirality in pure 2D perovskites for potential applications in circularly polarized light (CPL) emission and detection; nonetheless, studies on those aspects are still in their infancy. Here we report on the strong CPL emission and sensitive CPL detection in the visible wavelength range in pure chiral (R/S-MBA)2PbI4 (MBA=C6H5C2H4NH3) 2D perovskites, which are successfully synthesized with a needle shape and millimeter size by incorporating the chiral molecules. The chiral 2D perovskites (R-MBA)2PbI4 and (S-MBA)2PbI4 exhibit average degree of circularly polarized photoluminescence (PL) of 9.6% and 10.1% at 77 K, respectively, and a maxi...