Multilayered Alternating-Cations-Intercalation Chiral Hybrid Perovskites with High Circular Polarization Sensitivity

Multilayered chiral hybrid perovskites are highly desired for highly-sensitive circularly polarized light (CPL) detection rooted in their efficient charge transport and strong chiroptical activity. However, designing multilayered chiral hybrid perovskites remains a huge challenge. Here, through pairing achiral ethylamine (EA)-chiral arylamine in the interlayer space, multilayered chiral alternating cations intercalation-type (ACI) hybrid perovskites (R-/S-PPA) EA₂ Pb₂ Br₇ (PPA = 1-phenylpropylamine) are successfully obtained. Significantly, perovskitizer EA extends the thickness of the quantum well and alternating space cation EA greatly alleviates in-plane tilting distortions of adjacent metal halide octahedra, providing fast channels for in-plane carrier transport. Consequently, single-crystal photodetectors of (R-/S-PPA) EA₂ Pb₂ Br₇ exhibit high circular polarization sensitivity with a large anisotropy factor of 0.3, which falls around the highest value among the layered hybrid perovskites. In addition, a fast responding rate (τ_r )of 308 µs and a high CPL-detectivity of 8 × 10¹² Jones are also presented. This work opens up a new perspective to design multilayered chiral hybrid perovskites for high-sensitive CPL detection.