Hierarchical composite films with synergistic waterproof breathable and passive radiative cooling performance via nonsolvent-induced phase separation and electrospray

Integrating efficient passive daytime radiative cooling with superior waterproof and breathable performance within a single durable material system remains a critical challenge for developing all-weather protective and energy-saving materials. Here, we report an innovative and scalable strategy that synergistically combines nonsolvent-induced phase separation and electrospraying to construct hierarchically structured poly(vinylidene fluoride-co-hexafluoropropylene)/silica composite membranes. This hierarchical architecture strategically employs an interconnected microporous network to facilitate efficient water vapor transport while utilizing a nanoparticle-induced hierarchical surface to simultaneously enhance solar scattering and hydrophobicity. As a result, the film provides exceptional radiative cooling, achieving an approximately 7.4 °C temperature reduction attributed to a high solar reflectance of 96.1 % and an infrared emissivity of 92.5 %, while also offering superior waterproofness of 61 kPa and breathability of 4.57 kg·m −2 ·d −1 . More importantly, the film exhibits remarkable chemical durability under extreme acidic/alkaline conditions (pH 1–13). This structure-function matched design provides a versatile and industrially viable pathway for developing next-generation multifunctional materials with broad applications in personal thermal management, energy-efficient buildings, and outdoor protective equipment.