Efficiently increasing the radiative rate of TADF material with metal coordination.

Herein, a simple and straightforward method to reduce dramatically the lifetime of a pure organic thermally activated delayed fluorescence (TADF) material VIA metal coordination is demonstrated. We designed a mononuclear silver complex [Ag(PPh 2 CH 3 )(TCzBN-PyPz)]BF 4 (1) with a new emissive TCzBN-PyPz ligand. Even though the ligand and the metal complex have very similar emissive efficiencies and maximal peaks, over three orders of magnitude shorter lifetime of 0.59 μs for the complex than 2074 μs for ligand were obtained. Compared to other methods, the present protocol seems to be simple and highly effective.