Thermochromic Circularly Polarized Luminescence via Chiral AIEgen-loaded Microcapsules for Adaptive Camouflage and Security

Stimuli-responsive circularly polarized luminescence (CPL) materials show great promise for dynamic camouflage, information encryption, and smart sensing. However, synthesis complexity and limited practical versatility hinder current research. This study demonstrates novel thermochromic CPL microcapsules (MCs) that contain chiral aggregation-induced emission luminogens (AIEgens) doped alkane phase change materials (PCMs). The synthesized AIEgens, characterized by a high photoluminescence quantum yield of 73.3% and obvious chiroptical properties, were successfully incorporated into PCMs to form thermochromic CPL materials. Microencapsulation of the AIEgen-doped PCMs effectively addressed practical concerns of leakage and corrosion, yielding stable and thermally reliable MCs. These MCs exhibited versatility across diverse polymeric matrices and substrate surfaces, highlighting their adaptability. Leveraging the thermochromic CPL properties, 2D and 3D information encryption systems based on MC-embedded coatings were developed, ensuring high-level data security. Furthermore, their application in high-end camouflage effectively adapted military vehicle coatings to diverse environmental terrains, improving stealth and survivability. The easy scalable fabrication and multifunctionality of these thermochromic CPL MC-embedded coatings hold transformative potential for security and defense applications, offering innovative solutions for protecting sensitive information and concealing military assets.