Suchergebnisse

This project is supported by the Helmholtz Association Program at the Karlsruhe Institute of Technology. The German Research Foundation (formally Deutsche Forschungsgemeinschaft DFG) in the framework of SFB1176 Cooperative Research Centre "Molecular Structuring of Soft Matter" (CRC1176, A4, B3, C2, C6) and the cluster 3D Matter Made To Order funded under Germany's Excellence Strategy (3DMM2O EXC-2082/1-390761711) are greatly acknowledged for financial contributions. ZZ acknowledges the financial support from Chinese Scholarship Council (CSC) for his PhD studies. SK acknowledges the financial support from European Union's Horizon 2020 research and innovation programme under Marie Skłodowska Curie Individual Fellowship (MCIF; Agreement No. 748430-THF-OLED). S.B. acknowledges support from the Bayrisches Staatsministerium für Wissenschaft und Kunst (Stmwk) in the framework of the initiative "SolTech" as well as from the German Science foundation (DFG) (no. 392306670). ; Six luminophores bearing an OBO-fused benzo[fg]tetracene core as an electron-acceptor were designed and synthesized. The molecular structures of three molecules ( PXZ-OBO, 5PXZ OBO, 5DMAC-OBO ) were determined by single crystal X-ray diffraction studies and revealed significant torsion between the donor moieties and the OBO acceptor with dihedral angles between 75.5° and 86.2°. Photophysical studies demonstrate that blue and deep blue emission can be realized with photoluminescence maxima (λPL) ranging from 415 nm to 480 nm in mCP films. The emission energy is modulated by simply varying the strength of the donor heterocycle, the number of donors and their position relative to the acceptor. Although the DMAC-derivatives show negligible delayed emission due to their large singlet-triplet excited state energy difference, ΔEST, PXZ-based molecules, especially PXZ-OBO with an experimental ΔEST of 0.25 eV, demonstrate delayed emission in blend mCP films at room temperature, which suggests triplet exciton harvesting occurs in these samples, potentially by thermally activated delayed fluorescence (TADF). ; Publisher PDF ; Peer reviewed