Azobenzene‐based molecular solar thermal integrated with phase change materials for smart thermoregulating textiles

Abstract Molecular Solar Thermal (MOST) energy storage provides a molecular‐level route to convert intermittent sunlight into on‐demand heat via reversible photoisomerization of photoswitches. Azobenzene (Azo) and its derivatives stand out for wearable thermal management, as their photochemistry, thermal reversion kinetics, molecular packing, and interfacial interactions are amenable to systematic molecular engineering. We survey recent progress in azo‐based MOST textiles synergized with phase change materials (PCM), tracing the trajectory from molecular design to hybrid energy‐storage architectures and ultimately textile integration. Key strategies for enhancing azo energy storage are critically examined, including template confinement, polymer topology control, dynamic coordination, heteroaryl and ortho ‐substituent engineering, and alkyl‐chain‐mediated phase regulation. Particular emphasis is placed on Azo@PCM systems, in which the PCM matrix serves as a solid‐state solvent that promotes isomerization while contributing latent heat, enabling dual‐mode energy storage and light‐triggered heat release via controlled phase transitions. Representative textile fabrication methods, including coating, microencapsulation, electrospinning, wet‐spinning, coaxial spinning, and Janus architectures, are systematically reviewed. Persistent challenges in energy density, solar‐to‐thermal conversion efficiency, wearability, and scalable manufacturing are identified, offering perspectives for the rational design of next‐generation smart thermoregulating textiles.