Dresden 2017 – wissenschaftliches Programm
CPP 7: Organic Electronics and Photovoltaics I: Light-Emitting Devices (joint session CPP/DS/HL, organized by CPP)
CPP 7.2: Vortrag
Montag, 20. März 2017, 11:15–11:30, ZEU 260
Conjugation induced thermally activated delayed fluorescence — •Paul Kleine1, Qiang Wei2, Yevhen Karpov2, Xianping Qiu2, Hartmut Komber2, Karin Sahre2, Anton Kiriy2, Ramunas Lygaitis1, Simone Lenk1, Brigitte Voit2, and Sebastian Reineke1 — 1Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Dresden, Germany — 2Leibniz-Institut für Polymerforschung Dresden e.V., Dresden, Germany
Thermally activated delayed fluorescence (TADF) has seen tremendous research efforts in the last years. It represents an alternative to phosphorescent emitter materials in organic light-emitting diodes, assuring 100% internal quantum efficiency via effective reverse intersystem crossing of barely radiative triplet to emissive singlet states. While many small molecules have been reported to show efficient TADF, reports on polymers sporting TADF are rare. Up to now, publications cover concepts only, where TADF chromophores are linked to polymer networks, retaining their monomeric properties. In this talk, we discuss a novel strategy that unlocks an additional molecular design rule reserved exclusively for polymeric materials. A π-conjugated cyclic polymer composed of non-TADF building blocks was developed. Conjugation induced HOMO destabilization leads to a decreased singlet-triplet splitting and efficient TADF in the polymer, while the repeating unit shows only inefficient phosphorescence. This conjugation induced TADF concept represents a novel molecular design rule particularly for solution-processable polymeric materials.