Moisture-Resistant Chiral Perovskites for White-Light Circularly Polarized Photoluminescence

Circularly polarized luminescence (CPL) has recently caught increasing attention owing to its widespread applications from 3D display to quantum-based optical computation. Among various CPL-active materials, low-dimensional hybrid perovskites have risen to prominence, benefiting from their excellent structural flexibility and optoelectronic properties. However, the exploration of hybrid perovskites with white-CPL remains a challenge and most of them suffer from moisture instability. Here, a pair of moisture-resistant 1D hybrid perovskites, ( R -C 5 H 14 N 2 )PbBr 4 ·H 2 O ( 1R ) and ( S -C 5 H 14 N 2 )PbBr 4 ·H 2 O ( 2S ), are reported in which [PbBr 4 2− ] ∞ double chains are surrounded by chiral cations and water molecules forming the bulk assembled quantum-helix structures. The strong quantum confinement in these unique structures facilitates exciton self-trapping, which further synergizes the effect of chiral cations, endowing 1R and 2S with opposite broadband yellowish white-CPL with a luminescence dissymmetry factor ( g lum ) of 1.8 × 10 −3 and a color rendering index up to 81. Notably, the dehydrated 1R can be recovered in humid air (60% relative humidity) within a few minutes via reabsorption of water molecules, exhibiting excellent moisture resistance, which is much better than most reported hybrid perovskites. A new path is paved here to further exploration of moisture-resistant CPL-active materials for multifunctional applications.