Yangtao Shao, Xubin Wang, Hexi Wei, Xinli Li, Rongrong Huang, Shiwei Yin, Haonan Peng, Yu Fang
Concurrent thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) within one molecular family remain rare. Here we implement carborane-number engineering in o -carborane-functionalized triphenylamines (TPA-1Cb/2Cb/3Cb) to program the S 1 -T n landscape (S 1 = lowest singlet excited state; T n = low-lying triplet states). Increasing the carborane count reshapes S 1 -T n alignments and facilitates intersystem crossing and T n -assisted reverse intersystem crossing, while aggregate confinement suppresses nonradiative decay, enabling dual-channel emission. Spectroscopy and transient absorption establish solution-phase TADF for TPA-2Cb/3Cb and solid-state, air-robust TADF/RTP coexistence under ambient atmosphere with ultralong TADF lifetimes of 67.4 ms (TPA-2Cb) and 105.3 ms (TPA-3Cb). TD-DFT based on crystal structures attributes channel allocation to carborane-count-dependent tuning of Δ E (S 1 -T n ) and finite spin–orbit coupling (SOC), whereas TPA-1Cb remains RTP-dominant due to large S 1 -T 1 /T 2 separations. These results define a compact route to time-programmable, dual emission and offer a generalizable design principle for building concurrent TADF/RTP in carborane-based luminophores.