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‐C5H14N2)PbBr4·H2O (1R) and (S‐C5H14N2)PbBr4·H2O (2S), are reported in which [PbBr42−]∞ 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 (glum) 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. [ABSTRACT FROM AUTHOR]