Precise modulation of room-temperature phosphorescence through block copolymer self-assembly

Room-temperature phosphorescent (RTP) polymer materials have demonstrated significant potential for various applications. In this study, we synthesized a series of polyacrylamide (PAM)-based block copolymers (BCPs) exhibiting RTP emission. These copolymers are capable of emitting phosphorescence in both organic solvents and aqueous solutions. Notably, the afterglow of NaBCP-10 remains visible to the naked eyes even after being submerged in water for over five days. Furthermore, these block copolymers can self-assemble into various mesostructures, with tunable RTP performance. The lifetime of NaBCP-10 increases from 505.2 ms to 845.4 ms and then to 934.3 ms as the topology transitions from disordered to microspherical and finally to a porous structure. Using solubility parameter (SP) theory and molecular dynamics (MD) simulations, we demonstrate that the variations in nanostructure morphology and phosphorescent properties are primarily driven by the packing density of the hydrophilic core within the block copolymer. Importantly, we have successfully achieved both diversity and universality in this RTP-BCP system by modifying the components of the block copolymer. Additionally, these materials were employed to develop a range of anti-counterfeiting applications with distinct features.