Reconfigurable Multi-Stimuli Responsive Smart Phosphorescent Polymer Composites with Time-Dependent and...

Developing smart systems based on phosphorescent materials that can control the time-dependent phosphorescent color (TDPC) in response to external stimuli holds promise for advancing information encryption, but significant challenges remain. Herein, a facile strategy is proposed to construct smart phosphorescent polymer composites through immobilizing dual-emission centers with distinct stimuli sensitivities within a soft-rigid coupled hybrid matrix. The smart phosphorescent polymer composites show switchable phosphorescence between static phosphorescence and wavelength-dependent dynamic TDPC, induced by multi-stimuli (light, humidity, heat). The photoactivated phosphorescent composites transform from initial static monochromatic emission to dynamic multicolor TDPC through the synergistic effect of triplet oxygen depletion-induced selective activation of the emission centers and the distinct decay rates of the dual-emission centers. The evolution paths of TDPC also exhibit excitation-dependence. Moreover, the photoactivated composites enable reversible switching between dynamic TDPC and monochromatic phosphorescence through water and thermal stimuli, due to the combined effects of water-induced dissociation of the rigid hydrogen-bonding network and differential quenching of the dual-emission centers. The composites also exhibit recyclability and self-healing capability. The processable smart phosphorescent polymer composites with good stability demonstrate outstanding potential in multi-dimensional information encryption, opening up a new perspective for upgrading security technologies.