Organic Metal Halide Hybrids Research Articles

Sunlike White-Light-Emitting Diodes Based on Zero-Dimensional Organic Metal Halide Hybrids

Here we report ultraviolet (UV)-pumped white-light-emitting diodes (WLEDs) with sunlike full spectrum emissions, by using a commercially available blue phosphor (BaMgAl10O17:Eu2+) and a series of broadband zero-dimensional (0D) organic metal halide hybrids as down conversion phosphors. By controlling the blend ratio of phosphors, we have achieved high-quality WLEDs with excellent general color rendering index (CRI Ra) of up to 99 and deep-red rendering index (R9) of up to 99. These WLEDs exhibiting white emissions with correlated color temperatures (CCTs) ranging from 3000 to 6000 K perfectly mimic sunlight at different times of day.

Luminescent zero-dimensional organic metal halide hybrids with near-unity quantum efficiency.

Single crystalline zero-dimensional (0D) organic-inorganic hybrid materials with perfect host-guest structures have been developed as a new generation of highly efficient light emitters. Here we report a series of lead-free organic metal halide hybrids with a 0D structure, (C4N2H14X)4SnX6 (X = Br, I) and (C9NH20)2SbX5 (X = Cl), in which the individual metal halide octahedra (SnX64-) and quadrangular pyramids (SbX52-) are completely isolated from each other and surrounded by the organic ligands C4N2H14X+ and C9NH20+, respectively. The isolation of the photoactive metal halide species by the wide band gap organic ligands leads to no interaction or electronic band formation between the metal halide species, allowing the bulk materials to exhibit the intrinsic properties of the individual metal halide species. These 0D organic metal halide hybrids can also be considered as perfect host-guest systems, with the metal halide species periodically doped in the wide band gap matrix. Highly luminescent, strongly Stokes shifted broadband emissions with photoluminescence quantum efficiencies (PLQEs) of close to unity were realized, as a result of excited state structural reorganization of the individual metal halide species. Our discovery of highly luminescent single crystalline 0D organic-inorganic hybrid materials as perfect host-guest systems opens up a new paradigm in functional materials design.

Bulk assembly of organic metal halide nanotubes.

The organic metal halide hybrids welcome a new member with a one-dimensional (1D) tubular structure. Herein we report the synthesis and characterization of a single crystalline bulk assembly of organic metal halide nanotubes, (C6H13N4)3Pb2Br7. In a metal halide nanotube, six face-sharing metal halide dimers (Pb2Br95-) connect at the corners to form rings that extend in one dimension, of which the inside and outside surfaces are coated with protonated hexamethylenetetramine (HMTA) cations (C6H13N4+). This unique 1D tubular structure possesses highly localized electronic states with strong quantum confinement, resulting in the formation of self-trapped excitons that give strongly Stokes shifted broadband yellowish-white emission with a photoluminescence quantum efficiency (PLQE) of ∼7%. Having realized single crystalline bulk assemblies of two-dimensional (2D) wells, 1D wires, and now 1D tubes using organic metal halide hybrids, our work significantly advances the research on bulk assemblies of quantum-confined materials.