Multiple resonance (MR) effect induced thermally activated delayed fluorescence (MR-TADF) materials, specifically categorized for the framework of B/N and carbonyl/amine fragments, are now intensively and widely studied due to its...

Development of near-infrared (NIR)-emitting phosphorescent emitters are still urgent need for solution-processed organic light-emitting diodes (SP-OLEDs) with high efficiency and radiant emittance, low cost. Herein, we designed and synthesized...

Due to the limitation of energy gap law, platinum(II) complexes simultaneously with long luminous wavelength and high efficiency are still confronted with challenge. In order to better understand the effect...

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Hybridized local and charge‐transfer (HLCT) excited‐state emitters can effectively utilize non‐radiative triplet excitons through high‐lying reverse intersystem crossing (hRISC), but they are mostly limited to the donor‐π‐acceptor type molecules. It is a great challenge to develop high‐performance near‐ultraviolet (NUV) emitters with narrow‐band emission by HLCT due to the large carrier injection barriers and high triplet energy. In this work, by incorporating planar multi‐resonance (MR) skeleton of oxygen‐bridged triphenylborane (BO) and weak electron‐donating unit of tetraphenyl‐silane (TPS), two NUV emitters of tBOSi and tBOSiCz are developed, where an extra weak charge transfer (CT) channel between BO skeleton and peripheral phenyl in TPS is observed to increase CT component and activate hot exciton channel of hRISC. As a result, tBOSi and tBOSiCz show an outstanding narrow‐band NUV emission at 414 nm with a FWHM of about 32 nm in solution‐processed organic light‐emitting diodes (OLEDs), even at a heavy doping ratio. The best NUV electroluminescent properties are further achieved in the optimal tBOSi‐doped OLEDs with a record efficiency of 9.15% and a low CIEy of 0.034. This work provides a profound guidance for developing high‐performance narrow‐band NUV emitters by an extra weak CT channel into MR skeleton to activate HLCT emission.