Enantiomorphic Single Crystals of Linear Lead(II) Bromide Perovskitoids with White Circularly Polarized Emission

Chiroptical hybrid organic-inorganic perovskites are emerging as a new class of promising materials with mirror optical signal responses for optoelectronic applications. However, chiroptical white-emission materials have been scarcely unearthed. Herein, four pairs of hybrid lead(II) bromide perovskitoids were obtained, namely, (R)- and (S)-(H₂ MPz)PbBr₄ (R/S-MPz=(R)-(-)/(S)-(+)-2-methylpiperazine) (1 and 2), (R)- and (S)-(H₂ MPz)₃ Pb₂ Br₁₀ ⋅2 DMAc (3 and 4), (R)- and (S)-(H₂ MPz)PbBr₄ ⋅0.5 MeCN (5 and 6) and (R)- and (S)-(H₂ MPz)₂ Pb₂ Br₈ ⋅DCM (7 and 8). Notably, they all exhibit ultrabroadband emission and chiroptical signals. Perovskitoids 3-6 even achieve white circularly polarized emission with a high dissymmetric factor (g_lum ) (±3×10^-3 for 3 and 4; ±8×10^-3 for 5 and 6). This new type of hybrid perovskitoids will attract attention and find applications in chiroptical fields because of the extensively and easily tunable photophysical properties.