Reactivity of organic photocatalysts displaying thermally activated delayed fluorescence (TADF): rationalizing unexpected differences between rates of quenching of the lowest singlet and triplet states.

ABSTRACT: Cyanoarene chromophores exhibiting thermally activated delayed fluorescence (TADF) are increasingly used in photoredox catalysis. At high concentrations of organic substrates, which are typically employed in preparative synthesis, the primary photoinduced electron transfer (PeT) steps in the photocatalytic processes can involve both singlet (S₁) and triplet (T₁) excited states of TADF chromophores, despite very short lifetimes (nanoseconds) of the former. However, the difference between the reactivities of these states is not well understood, while being critically important for the photocatalytic process. In this work, three representative TADF chromophores were examined in reductive and oxidative PeT quenching reactions. First, using kinetic simulations, we assert t

SUBMITTER: Fina F 

PROVIDER: S-EPMC12501882 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature