2250280-17-0

2PTZBN is a multi-resonance thermally activated delayed fluorescence (MR-TADF) green emitter featuring a DABNA-1 triarylboron core. Two heavy sulfur atoms are incorporated opposite the nitrogen atoms to bridge the peripheral phenyl rings, resulting in a more rigid molecular structure. By incorporating non-metal sulfur atoms into the multi-resonance B–N framework, 2PTZBN can accelerate the reverse intersystem crossing (RISC) rate to up to 2.8 × 10^5 s⁻¹ in toluene, owing to its larger spin–orbit coupling (SOC) and smaller singlet–triplet energy splitting (ΔE_ST), compared with the oxygen-incorporated green MR-TADF emitter 2PXZBN (PXZ-BN).

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