Chiral Gadolinium Halides with Narrow Ultraviolet B Circularly Polarized Luminescence

Abstract Circularly polarized luminescence (CPL) in the ultraviolet B (UVB) region holds great potential applications in asymmetric catalysis, enantioselective polymerization, and polarization‐based optical anticounterfeiting and information encryption. However, to date, the CPL materials in the UVB region remain unexplored. In this study, the first chiral gadolinium‐based organic–inorganic hybrid metal halides, ( R / S ‐C 3 H 7 NF 3 ) 3 GdCl 6 ( R / S ‐ 3F ‐ Gd ), were constructed, which exhibit efficient CPL in the UVB region. Owing to the unique 4 f ‐4 f transition of Gd 3+ ions, R / S ‐ 3F ‐ Gd shows a high photoluminescent quantum yield of 18%, a narrow full width at half maximum (∼3 nm) and a ultralong photoluminescence lifetime (∼6.6 ms). Additionally, their CPL can be further tuned by applying the external magnetic field. Then the light‐emitting diode (LED) chips coated with R ‐ or S ‐ 3F ‐ Gd were also fabricated, which exhibit high dissymmetry factor of + 9.1 × 10 −3 and −8.2 × 10 −3 , further demonstrate their potential as circularly polarized light source in the UVB region. Our work offers a novel strategy for designing the chiral luminescent materials with efficient CPL response in the UVB region and broadens the family of chiral organic–inorganic hybrid rare‐earth halides.