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  1. 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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    Free, publicly-accessible full text available March 23, 2024
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  3. null (Ed.)
  4. Abstract

    Zero‐dimensional (0D) organic metal halide hybrids (OMHHs) have recently emerged as a new class of light emitting materials with exceptional color tunability. While near‐unity photoluminescence quantum efficiencies (PLQEs) are routinely obtained for a large number of 0D OMHHs, it remains challenging to apply them as emitter for electrically driven light emitting diodes (LEDs), largely due to the low conductivity of wide bandgap organic cations. Here, the development of a new OMHH, triphenyl(9‐phenyl‐9H‐carbazol‐3‐yl) phosphonium antimony bromide (TPPcarzSbBr4), as emitter for efficient LEDs, which consists of semiconducting organic cations (TPPcarz+) and light emitting antimony bromide anions (Sb2Br82−), is reported. By replacing one of the phenyl groups in a well‐known tetraphenylphosphonium cation (TPP+) with an electroactive phenylcarbazole group, a semiconducting TPPcarz+cation is developed for the preparation of red emitting 0D TPPcarzSbBr4single crystals with a high PLQE of 93.8%. With solution processed TPPcarzSbBr4thin films (PLQE of 86.1%) as light emitting layer, red LEDs are fabricated to exhibit an external quantum efficiency (EQE) of 5.12%, a peak luminance of 5957 cd m−2, and a current efficiency of 14.2 cd A−1, which are the best values reported to date for electroluminescence devices based on 0D OMHHs.

     
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