Thermally activated delayed fluorescent emitters based on 3-(phenylsulfonyl)pyridine

3-(Phenylsulfonyl)pyridine (PSP), an unreported acceptor, is used to construct two thermally activated delayed fluorescent materials (TADF), PSPP and PSPBP, with rigid PXZ as donor in 3-position or 3, 5-position of PSP. Both PSPP and PSPBP have large twisted structure due to highly steric hindrance, resulting in small ΔEST. Simultaneously, the frontier molecular orbitals of PSPP and PSPBP show limited spatial overlap, which improve photoluminescence quantum yields. Both emitters have distinct TADF performance. The OLEDs based on these emitters exhibit good photoelectric properties. This work enriches the acceptor selection scope and possesses crucial significance to developing new TADF molecules.