Epoxy Network Hosts Confine Small Molecule Guests for Enhancing Phosphorescence Through F‐π and π‐π Synergistic Interactions

ABSTRACT Organic room‐temperature phosphorescent (RTP) materials have attracted significant interest in information security and anti‐counterfeiting due to their unique afterglow properties. However, the role of non‐covalent interactions in enhancing phosphorescence remains insufficiently explored. Herein, we report a composite coating based on the synergistic effects of F‐π and π‐π stacking interactions within a dual‐phase 3D covalently cross‐linked network, by confining small molecular guests within an epoxy network host. The coating exhibits an ultra‐long room‐temperature phosphorescence (URTP) lifetime of up to 5.40 s, representing the longest lifetime reported in an epoxy resin system. The coating also displays switchable URTP and excellent surface characteristics, enabling the creation of rewritable anti‐counterfeiting labels through light‐activated printing and thermal erasure. Its low surface energy (15.85 mN·m −1 ) and self‐cleaning ability ensure the long‐term stability and concealment of encoded information. This work highlights the efficacy of engineering non‐covalent interactions for the development of high‐performance, erasable organic phosphorescent materials in anti‐counterfeiting applications.