Researchers emonstrate that even a small modulation in molecular geometric structures greatly affects concentration quenching of thermally activated delayed fluorescence (TADF) and can enhance the quantum efficiencies of solid-state photoluminescence (PL) and electroluminescence (EL). The exciton-quenching rates of TADF emitters show an exponential dependence on their intermolecular distance in thin films, revealing that electron-exchange interactions of triplet excitons, as described by the Dexter energy-transfer model, dominate the concentration quenching of TADF. This mechanism stands in marked contrast to those of conventional fluorescent and phosphorescent emitters involving Förster energy transfer.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering