High Quantum Yield and High‐Contrast Mechanofluorochromic Materials for Visualization of Details in Latent Fingerprints and Advanced Information Encryption Applications

ABSTRACT Organic aggregation‐induced emission (AIE) molecules combining high quantum yield with high‐contrast mechanofluorochromism (MFC) represent a promising class of materials for advanced applications in latent fingerprints (LFPs) visualization and secure information encryption. However, the rational design of such multifunctional materials presents significant challenges. In this study, two pyrene‐functionalized donor‐acceptor (D‐A) type bis‐aryl methanone derivatives, namely PMCZ and PMTPA , were successfully synthesized. Comprehensive theoretical analysis reveals: (1) substantial intramolecular potential differences, and (2) characteristic spatial separation of frontier molecular orbitals—key features of effective D‐A systems. The PMTPA crystal exhibits a high quantum yield of 62.4% and adopts a unique anti‐parallel dimer configuration (with an interplanar distance of 3.454 Å and an overlap area of 65.8%), which significantly amplifies intermolecular π–π interactions. Upon external force stimulation, the material undergoes a distinctive response mechanism: (1) initial packing structure slippage, (2) disruption of C−H···O hydrogen‐bonded networks, and (3) consequent crystalline‐to‐amorphous phase transition, collectively producing a remarkable 51 nm emission shift for high‐contrast mechanofluorochromism. Practical application confirms that material PMTPA possesses both latent fingerprints visualization and dynamic information storage functions, enabling a complete solution from biometric collection to information encryption and providing a new type of intelligent material for the field of public security.