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, (C 6 H 13 N 4 ) 3 Pb 2 Br 7 . In a metal halide nanotube, six face-sharing metal halide dimers (Pb 2 Br 9 5− ) 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 (C 6 H 13 N 4 + ). 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.
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One-dimensional organic metal halide nanoribbons with dual emission
Organic metal halide hybrids with low-dimensional structures at the molecular level have received great attention recently for their exceptional structural tunability and unique photophysical properties. Here we report for the first time the synthesis and characterization of a one-dimensional (1D) organic metal halide hybrid, which contains metal halide nanoribbons with a width of three octahedral units. It is found that this material with a chemical formula C 8 H 28 N 5 Pb 3 Cl 11 shows a dual emission with a photoluminescence quantum efficiency (PLQE) of around 25%. Photophysical studies and density functional theory (DFT) calculations suggest the coexisting of delocalized free excitons and localized self-trapped excitons in metal halide nanoribbons leading to the dual emission.
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- Award ID(s):
- 2204466
- PAR ID:
- 10430067
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 59
- Issue:
- 25
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 3711 to 3714
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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