Ultrafast Triplet–Singlet Exciton Interconversion in Narrowband Blue Organoboron Emitters Doped with Heavy Chalcogens

Abstract Narrowband emissive organoboron emitters featuring the multi‐resonance (MR) effect have now become a critical material component for constructing high‐performance organic light‐emitting diodes (OLEDs) with pure emission colors. These MR organoboron emitters are capable of exhibiting high‐efficiency narrowband thermally activated delayed fluorescence (TADF) by allowing triplet‐to‐singlet reverse intersystem crossing (RISC). However, RISC involving spin‐flip exciton upconversion is generally the rate‐limiting step in the overall TADF; hence, a deeper understanding and precise control of the RISC dynamics are ongoing crucial challenges. Here, we introduce the first MR organoboron emitter ( CzBSe ) doped…

• JS
  Japan Society for the Promotion of Science

  Awards: JP21H04694, JP19K15651, JP18H02048
• JS
  Japan Science and Technology Agency

  Award: JPMJCR21O5