Frequency resolved photoluminescence (PL), delayed fluorescence and triplet-triplet annihilation in π-conjugated polymers

摘要

The delayed fluorescence of poly(p-phenylene vinylene) (PPV) and poly(p-phenylene ethynylene) (PPE) derivative solids and frozen solutions at 20 K is described. It provides strong evidence for triplet-triplet annihilation to singlets excitonsaccounting for up to ～3% of the total emission in PPV films and ～1.5% in PPE powder. It also yields triplet lifetimes of 70 and 110μs in PPV films and frozen solutions, and ～200 and ～500μs in PPE powder and frozen solutions, respectively.