Constructing Stretchable Superhydrophobic Perovskite Quantum Dot Films via Dual-Phase Synergistic Engineering.

Perovskite quantum dots (PQDs) films intended for flexible optical applications are required not only to exhibit excellent luminescence performance, but also to simultaneously possess high stretchability, superhydrophobicity, patterned luminescence, and multicolor programmability under complex conditions such as large deformation, liquid intrusion, and long-term service. Here we propose a dual-phase synergistic engineering strategy, and in combination with replica molding and femtosecond laser direct writing technologies, achieve the construction of a biomimetic superhydrophobic surface and the controllable precipitation of PQDs while endowing the film with superelasticity. Benefiting from the dual-phase structure and biomimetic surface design, the film still retains more than 52% of its initial luminescence intensity and a water contact angle above 150° under 800% tensile deformation. This strategy is applicable to full-spectrum luminescent systems spanning 470-688 nm and supports proof-of-concept binary optical encoding. After continuous immersion in water for 240 days, the film still retains more than 90% of its initial luminescence intensity and more than 95% machine-learning recognition accuracy. This work provides a new strategy for the design of multifunctional flexible PQDs films with stable luminescence under deformation and water exposure.