Tetrazolate-based neutral Cu(I) complex for efficient and short-lived blue thermally activated delayed fluorescence

Endowing thermally activated delayed fluorescence (TADF) emitters simultaneously with high emission quantum yields and short radiative lifetimes is of fundamental significance in optoelectronic field. In this contribution, two neutral tetrahedral Cu(I) complexes (1 and 2) have been developed, which realize blue-TADF with photo-luminescent quantum yield of up to 85 % due to the high structural rigidity. Meanwhile, short TADF lifetimes (<10 mu s) of the Cu(I) complexes suggest that the synergistic effects of small Delta E(S1-T1) gap and relatively large SOC value introduced by the copper ion could facilitate fast reverse ISC processes compared to the typical organic-TADF materials.