One-Dimensional Organic–Inorganic Lead Bromide Hybrids with Excitation-Dependent White-Light Emission Templated by Pyridinium Derivatives

Abstract

Organic−inorganic hybrid metal halides have attracted widespread attention due to their excellent tunability and versatility. Here, we have selected pyridinium derivatives with different substituent groups or substitution positions as the organic templating cations and obtained six 1D chain-like structures. They are divided into three types: type I (single chain), type II (double chain), and type III (triple chain), with tunable optical band gaps and emission properties. Among them, only (2,4-LD)PbBr 3 (2,4-LD = 2,4-lutidine) shows an exciton-dependent emission phenomenon, ranging from strong yellow-white to weak redwhite light. By comparing its photoluminescence spectrum with that of its bromate (2,4-LD)Br, it is found that the strong yellow-white emission at 534 nm mainly came from the organic component. Furthermore, through a comparison of the fluorescence spectra and lifetimes of (2,4-LD)PbBr 3 and (2-MP)PbBr 3 (2-MP = 2-methylpyridine) with similar structures at different temperatures, we confirm that the tunable emission of (2,4-LD)PbBr 3 comes from different photoluminescent sources corresponding to organic cations and self-trapped excitons. Density functional theory calculations further reveal that (2,4-LD)PbBr 3 has a stronger interaction between organic and inorganic components compared to (2-MP)PbBr 3 . This work highlights the importance of organic templating cations in hybrid metal halides and the new functionalities associated with them.

A 3D lead chloride hybrid exhibits self-trapped emission and exceptional stability

“…The results revealed similar PL spectra, indicating that the broadband emission of (H 2 MPP) 2 Pb 5 Cl 14 was caused by defects in the crystal surface position. All of the foregoing results, including the highly distorted structure, broadband emission, large Stokes shift, intense electronphonon interaction and previously reported Pb-based compounds with broadband emission, [53][54][55] strongly suggest that the observed white-red emission for (H 2 MPP) 2 Pb 5 Cl 14 SCs is a typical feature of STE recombination.…”

Increasing the Structural Rigidity and Quantum Yield of Highly Emissive Hybrid Antimony Chlorides Using a Diverse Set of Solvent Guests

“…[1][2][3][4][5][6] The 3D structure can be tailored into lower dimensionality via utilization of bulky DOI: 10.1002/adom.202303230 organic cations, resulting in a vast diversity of materials with highly tunable properties. [7][8][9][10][11][12] To further advance and expand the materials space, main-group metals with ns 2 lone pairs, primarily Ge 2+ , Sn 2+ , Sb 3+ , Bi 3+ , and Te 4+ are ideal alternatives for Pb 2+ substitution and potentially generate more interesting functionalities. [13][14][15][16][17][18][19] These materials often form 0D hybrid metal halides with large organic cations.…”