Single-Component White Circularly Polarized Luminescence in Chiral 1D Double-Chain Perovskites

摘要

Circularly polarized luminescence (CPL) with polychromatic colors has beenwidely studied due to its great applications in chiroptical, optoelectronics,and spintronics. However, the realization of white CPL in single-componentsolid-state materials remains a great challenge and suffers from the incompatibilitybetween high efficient luminescence and large asymmetric discrimination.Here, by exploiting self-trapped exciton mechanism and chiralityinduction strategy, a pair of 1D chiral perovskites, (RR/SS-DMPZ)PbBr4(where DMPZ = cis-2,5-dimethylpiperazine divalent cation), is reported toachieve white CPL with both high quantum yield of 28.4% and large photoluminescenceasymmetry factor |g_(lum)| of 2.32 × 10~(?2). The crystal structures arefeatured by 1D double-chain structure composed of distorted octahedra withshort PbPb distances as the structural origin of the high photoluminescenceyield. The high |g_(lum)| value is caused by efficient chiral induction due to themultiple hydrogen bonds between the chiral host composed of the enantiopureorganic cations containing two stereocenters and the inorganic emittingguest. The self-trapped exciton emission mechanism is demonstratedby density functional theory calculations and variable-temperature photoluminescenceand femtosecond-transient absorption spectroscopy studies.The photo-luminescent white light-emitting diodes exhibit good stability andcan be used as single-component white light emitters. This work providesapplicable strategies to explore single-component white CPL emitters.