Activating Ultralong Room‐Temperature Phosphorescence of Mono‐Ring Arylboronic Acid by Hydrogen Bond for Tunable Afterglow Color and Stimulus Response

Abstract Activating the ultralong room‐temperature phosphorescence (RTP) of mono‐ring arylboronic acid remains a great challenge, because the capacious free spaces shaped by a rubbery polymeric matrix allow the benzene ring skeleton to freely rotate. Herein, the ultralong RTP in mono‐ring arylboronic acid derivatives embedded in a polyvinyl alcohol (PVA) matrix is activated, leveraging enhanced intermolecular and intramolecular hydrogen bonding and activating ultralong RTP. By incorporating diverse PBA derivatives into PVA via click chemistry, 3‐aminophenylboronic acid (3A‐PBA) doped PVA films showcase the most extended RTP lifetimes (2.24 s) and a high quantum yield (11.2%), alongside rapid and sensitive explosive vapor detection capabilities. These findings not only address the activation challenges of RTP in organic systems by highlighting the crucial role of hydrogen bonding and Förster resonance energy transfer in color tunability, but also mark a significant stride toward overcoming the limitations of current luminescent materials. This work heralds a new era in the development of organic phosphorescent materials, offering a promising strategy for broadening their practical applications and enhancing performance, particularly in environmental monitoring and security.