Dendritic Carbene Metal Carbazole Complexes as Photoemitters for Fully Solution-Processed OLEDs

• DOI: 10.1021/acs.chemmater.8b05112
• Publication Date: 2019-04-26T21:45:23Z
• Authors: Alexander S. Romanov; Le Yang; Saul T. E. Jones; Dawei Di; Olivia J. Morley; Bluebell H. Drummond; Antti P. M. Reponen; Mikko Linnolahti; Dan Credgington; Manfred Bochmann
• Keywords: Carbazole; Quantum yield

Light-emitting carbene-metal amide complexes bearing first- and second-generation carbazole dendron ligands are reported, (AdL)M(Gn), (M = Cu Au; Gn dendrimer generation, where n 1 2; AdL adamantyl-substituted cyclic (alkyl)(amino)carbene). The thermal stability of the increases with each generation. Cyclic voltammetry indicates that highest occupied molecular orbital/lowest unoccupied orbital energy levels largely unaffected by size dendron, while first reduction oxidation processes show a quasi-reversible character. gold in toluene at room temperature photoluminescent quantum yields up to 51.5% for 78% second Varied transient photoluminescence decay is consistent thermally activated process, indicating delayed fluorescence-type emission mechanism. Neat films excited state lifetimes composed prompt dominant sub-microsecond components, radiative constants 106 s–1. Solution-processed organic light-emitting diodes first-generation copper dendrimers (AdL)M(G1) have been fabricated external efficiencies 5.5% 10.3% practical brightness.