Organic cations directed 1D [Pb3Br10]4− chains: syntheses, crystal structures, and photoluminescence properties

Abstract

Recently, low-dimensional organic–inorganic hybrid metal halides have attracted considerable attention in solid-state optical application fields, especially in white-light emitting diodes (WLEDs) owing to intrinsic broadband luminescence performances. Herein, by selecting different types of organic cations as a structural decoration strategy, we designed a series of new 1D hybrid halides of A₂Pb₃Br₁₀ (A = NPM, DMPDA, TMEN) based on same [Pb₃Br₁₀]⁴⁻ chains composed of edge-shared [Pb₃Br₁₂]⁶⁻ trimers. The low-dimensional crystal lattice results in the formation of self-trapped excitons, which leads to broadband light emissions covering the entire visible region for all A₂Pb₃Br₁₀ homologues. Specifically, compound 1 exhibits yellowish-white light emission (0.34, 0.45) with a photoluminescence quantum efficiency of 2.51%. Both compounds 2 and 3 show bluish-white light emissions centered at 438 nm and 440 nm, respectively, with high color rendering index (CRI) of 96, which belongs to one of the highest values to date. The intrinsic broadband white light emissions enable them as promising candidates for single-component white-light emitting materials.