Shear Stiffening‐Based Mechanoluminescent Device for Impact‐Thermal Coupling Protection and Impact Visualization

Abstract Intelligent impact‐protection wearable devices often require intricate circuitry to operate, which hinders the timely display of impact‐related injuries. Consequently, it is imperative to develop intelligent protective materials that are self‐sufficient and capable of visualization. In this work, the impact protection material shear‐stiffening gel (SSG) is combined with the mechanoluminescent (ML) material ZnS:Cu/PDMS@SiO₂ to create ML‐SSG. This material embodies various protective features, including impact protection, force visualization, flame resistance, and long‐distance passive control, making it ideal for intelligent wearable devices. In light of the significant shear stiffening effect of SSG, ML‐SSG effectively dissipates up to 80% of the impact energy and exhibits excellent impact resistance. Concurrently, ML‐SSG is also capable of visualizing impact injuries, displaying and warning in real‐time via mechanoluminescence, and assessing the impact force based on the intensity of mechanoluminescence. The incorporation of SiO₂ and ZnS:Cu has resulted in ZnS:Cu/PDMS@SiO₂ with remarkable flame‐retardant property. This innovative material significantly improves the performance of ML‐SSG in complex environments. In addition, ML‐SSG realizes human–computer interaction through neural network based on mechanoluminescence display characteristics. This research significantly expands the potential applications of multifunctional protective materials in various complicated environments, thereby promoting the development of wearable protective devices.