White-light-emitting chiral materials represent a promising class of photoactive materials with great potential for optoelectronic and spintronic applications. Here, we report a series of white-light-emitting chiral two-dimensional (2D) organic metal halide hybrids (OMHHs), (R-/S-3XMBA)2PbBr4 (X = F, Cl, Br), synthesized from meta-position-halogen-substituted α-methylbenzylammonium (MBA) bromide salts and lead bromide (PbBr2). By tuning noncovalent hydrogen bonding, halogen–halogen, and halogen−π interactions at the organic–metal halide interfaces, we achieve systematic control over the structural rigidity and octahedral distortion within the inorganic layers. Among these materials, (R/S-3BrMBA)2PbBr4 exhibit broadband emissions centered around 535 nm, with large full widths at half-maximum (FWHMs) of ∼230 nm and the highest photoluminescence quantum efficiencies (PLQEs) of ∼30%, attributed to their high rigid crystal packing and optimal structural distortion within their inorganic sublattices. These materials also display pronounced chiroptical activity, with (R/S-3BrMBA)2PbBr4 exhibiting a gCD of ∼1.42 × 10–3 at 390 nm and (R-3FMBA)2PbBr4 achieving a record gCD of ∼1.49 × 10–2 at 394 nm, among the highest reported for chiral 2D OMHHs. This work establishes an effective molecular design strategy to simultaneously realize broadband white-light emission and robust structural chirality in 2D OMHHs, paving the way toward multifunctional chiral light-emitting materials.
Das et al. (Tue,) studied this question.