Delayed Fluorescence (DF) and Photoluminescence (PL)-Detected Magnetic Resonance (PLDMR) Studies of Triplet-Triplet (T-T) Annihilation and Other Long-Lived Processes in # pi #-Conjugated Polymers

摘要

Recent studies of frequency resolved DF due to T-T annihilation to singlet excitons (~1s) in # pi #-conjugated polymers are reviewed, and the significance of this process is compared to that of other long-lived processes affecting the PL, in particular the nonradiative quenching of ~1s by polarons or triplet excitons. While the DF studies suggest that T-T annihilation typically accounts for up to approx 3 percent of the total PL, PLDMR and other studies suggest that singlet quenching by polarons and triplets may be a very significant process in the films and organic light emitting devices (OLEDs), especially at high excitation densities.