Long‐Lived Organic Room‐Temperature Phosphorescent Fluids via Chromophore Confinement

ABSTRACT Fluidic room‐temperature phosphorescence (RTP) materials with tunable viscosity and distinctive triplet excited‐state properties hold considerable potential for applications in flexible electronics. However, realizing long‐lived fluid RTP remains highly challenging because the dynamic nature of fluid media enables extensive molecular motion and oxygen permeation, which readily dissipate chromophore triplet excitons via nonradiative pathways. Herein, we report a universal strategy for achieving room‐temperature phosphorescent polymer fluids through chromophore confinement within microphase‐separated domains of block copolymers. The localized confinement environments generated by rigid segments surrounding the chromophores effectively suppress nonradiative transitions and stabilize triplet excitons in the fluid state. Consequently, the resulting polymer fluids exhibit tunable viscous flow behavior and ultralong phosphorescence lifetimes of up to 364 ms. Moreover, the generality of the strategies is demonstrated by modulating chromophore structures and achieving a series of multicolor RTP polymer fluids. Leveraging their excellent fluidity and persistent afterglow emission, these materials demonstrate significant potential for adaptive afterglow displays and visualization detection. This work establishes an effective approach for constructing fluidic RTP polymer materials and offers new insights into the design of functional RTP materials.