Broadband White-Light Emission in One-Dimensional Organic–Inorganic Hybrid Silver Halide

Abstract

In the past few decades, organic–inorganic hybrid metal halides acting as single-component white light emission diodes (LEDs) have attracted extensive attentions, but most of the studies concentrate on the low-dimensional lead perovskites. Here, by using the nontoxic silver as optically active metal center, a series of hybrid silver halides based on one-dimensional structures were constructed and realized broadband white light emission. Compounds [H2DABCO]­[Ag2X4(DABCO)] (X = Br (1), I (2)) feature one-dimensional [Ag2X4(DABCO)]2– structures charged balanced by [H2DABCO]2+ cations. Compound 1 exhibits an efficient broadband white-light emission with photoluminescence quantum efficiency (PLQE) of about 2.1% and excellent photochemical stability, while compound 2 gives a broadband yellow-white emission centered at 556 nm. [HDABCO]3Ag5Cl8 (3) gives a strong broadband yellow emission (585 nm) with high PLQE of 6.7%, which can be easily fabricated as a white light emitting device. Based on the temperature-dependent, particle-size-dependent, and time-resolved PL measurements as well as other detailed studies, the broadband white-light emissions are ascribed to the synergetic effects of the organic and inorganic components. Our work provides a unique structural assembly method to explore lead-free single-component white-light illuminants from molecular level.

(NH4)2AgX3 (X = Br, I): 1D Silver Halides with Broadband White Light Emission and Improved Stability

“…21,22 Independent from the A 2 AgX 3 family, there has also been an increasing interest in hybrid variants of ternary silver halides, such as the white light emitting (H 2 DABCO)[Ag 2 X 4 (DABCO)] and (HDAB-CO) 3 Ag 5 Cl 8 . 23 These all-inorganic and hybrid compounds have set the stage for ternary silver halides as potential white light emitters, with high PLQY values up to 27%. 21 Here, we report the preparation and characterization of (NH 4 ) 2 AgX 3 (X = Br and I).…”

“…Despite their outstanding optical emission properties, the members of the A 2 CuX 3 family are all blue emitters and substitutions on the A and X sites in A 2 CuX 3 have shown only negligible impacts on the optical properties. ,,,, Such unusual lack of tunability of the photoluminescence (PL) properties in the A 2 CuX 3 family is due to the fact that electronic transitions take place primarily between copper­(I) orbitals. , To bring PL tunability to this family, a strategy based on the substitution of Cu­(I) with alternative metals (e.g., with Ag) is proposed. The validity of this approach was recently demonstrated for the A 2 AgX 3 (A = Rb, Cs; X = Cl, Br), which exhibit tunable broadband emission spectra attributed to STEs and defect-bound excitons (DBEs). , Independent from the A 2 AgX 3 family, there has also been an increasing interest in hybrid variants of ternary silver halides, such as the white light emitting (H 2 DABCO)­[Ag 2 X 4 (DABCO)] and (HDABCO) 3 Ag 5 Cl 8 . These all-inorganic and hybrid compounds have set the stage for ternary silver halides as potential white light emitters, with high PLQY values up to 27% …”

Realizing Tunable White Light Emission in Lead-Free Indium(III) Bromine Hybrid Single Crystals through Antimony(III) Cation Doping

“…Organic–inorganic metal halide hybrids (OIMHs) have emerged as unique semiconductors for various optoelectronic applications such as solar cells, − light-emitting diodes, − photodetectors, , and lasers. , Lowering the structure from three- (3D) to two- (2D), one- (1D), and zero-dimensional (0D) can enhance the exciton–phonon coupling to cause Jahn–Teller-like structural distortion in the lattice. As a result, excitons are transiently self-trapped, forming the so-called self-trapped excitons (STEs). − The distortion of the self-trapped state with respect to the ground state contributes to the broad emission with a large Stokes shift. , Having the advantages of easy processing, low cost, and broadband emission, these low-dimensional (2D, 1D, and 0D) OIMHs are promising luminescent materials for solid-state lighting; especially, they are considered as single-component white-light emitters. , …”

One‐Dimensional Molecular Metal Halide Materials: Structures, Properties, and Applications

“…Very recently, Sun and coworkers reported for the first time the synthesis of Ag‐based organic–inorganic hybrid C 6 H 13 N 2 AgBr 2 , where the 1D [Ag 2 Br 4 (DABCO)] 2− (DABCO = N 2 (C 2 H 4 ) 3 ) chain is separated by organic [H 2 DABCO] 2+ cations. [ 61 ] The reported compound exhibits outstanding photochemical stability with A PLQY of about 2.1%. Clearly, further research efforts are needed to explore and optimize the photochemical properties of such 1D metal halide hybrids and improve its operational stability.…”