Triplet-Induced Stable Organic Radical Emitter in Host-Guest Room-Temperature Phosphorescent Materials

Abstract New strategies for the synthesis of stable organic luminescent radicals with their unique electronic structures are highly desirable. Herein, we designed and synthesized a novel arylboron compound BN-2Ph with radical-generating potential. BN-Ph was used as the guest molecule in the host-guest system, exhibiting high-efficiency and persistent phosphorescent emission. The long lifetime triplet exciton induced unexpected luminescent radicals with red emission in the doped crystalline state, which could be rapidly and reversibly generated by heating and recrystallizing. The quantitative electron paramagnetic resonance analysis and theoretical calculations suggest that the triplet-stabled photoinduced electron transfer mechanism between host and guest molecules is responsible for the generation and stabilization of radicals. This doped system was applied in AND and OR logic gates, showing its potential application in logic circuits. Our results provide a simple molecular-design strategy for achieving stable organic luminescent radicals.