2026/07/27 by Wei Hong, Tao Chai, Le Ma +5
paper · doi:10.1002/app.71224
ABSTRACT In response to the bottlenecks of high cost, solvent pollution, and poor environmental adaptability of Passive Daytime Radiative Cooling (PDRC) materials, this study innovatively developed a PTFE/CaF 2 /TiO 2 ‐PVDF composite porous membrane via wet non‐solvent induced phase separation (NIPS) technology. Low‐temperature plasma modification was employed to enhance the dispersibility of PTFE. Combined with a DMF‐based solvent system and a three‐stage gradient recycling process, green preparation was achieved (solvent recovery rate of 91.8%, volatile organic compounds (VOCs) emissions reduced to 1.04 kg t −1 ); the synergistic substitution with PTFE/CaF 2 reduced raw material costs by approximately 28%, while maintaining high infrared emissivity. The resulting film (500 μm) exhibits excellent optical properties (reflectance of 99.7% in the 0.4–2.5 μm visible‐NIR band, peak emissivity of 0.967 in the 7–14 μm atmospheric window) and notable cooling performance (peak sub‐ambient temperature drop of 8.0°C under 1350 W m −2 solar irradiance, a 75% improvement over pure PVDF). Gradient TiO 2 (20 nm–1 μm) imparts UV shielding and anti‐fouling functionality; the micro‐nano porous structure (contact angle 98°) synergistically delays UV aging. This research provides a low‐cost and scalable radiative‐cooling material platform with potential applications in building energy efficiency, electronic thermal management, and photovoltaic thermal management.