An axially chiral TADF emitter, 4tBuCzPN, with a dual emitting core was easily synthesized. Compared with the TADF emitter 2tBuCzPN with the PLQY of 29% and EQE of 5.3%, 4tBuCzPN showed a significantly increased PLQY (74%) and EQE (20.8%) for its OLED. Moreover, the enantiomers of 4tBuCzPN also exhibited mirror-image CD and CPL properties, and the g_lum values of (+)-4tBuCzPN and (−)-4tBuCzPN were +5.4 × 10⁻³ and −5.0 × 10⁻³ in toluene, respectively.