Abstract: The accelerating pace of global warming critically undermines thermal comfort during elevated temperatures. Although cooling technologies are widely accessible, their use unavoidably escalates energy consumption and exacerbates the greenhouse effect. Passive radiative cooling (PRC), a zero-energy cooling technology, represents a vital strategy for advancing sustainable development. This study successfully fabricated a flexible FPEEK/PVDF-HFP/SiO₂ composite film (FPS film) that integrates PRC with energy harvesting by employing phase transition techniques in conjunction with micro/nanoengineering. Due to its precisely engineered architecture and carefully selected constituent materials, the FPS film demonstrated a high solar reflectance of 97.36 % (0.25-2.5 µm) and a strong atmospheric window emissivity of 93.04 % (8-13 µm), achieving theoretical net cooling powers (P_net) of 78.7 W m^-2 during daytime conditions and 119.0 W m^-2 at night. Both experimental evaluations and simulation analyses validated that the FPS film exhibited remarkable radiative cooling performance in architectural and transportation applications. Notably, the FPS film demonstrated efficient energy harvesting in hydrophobic triboelectric nanogenerators, reaching a peak power density of 525.3 mW m^-2, broadening its practical application scope. This study provides significant insights into the design and fabrication of next-generation integrated materials for radiative cooling and energy harvesting, thereby supporting efforts toward achieving carbon neutrality.

Key words: Passive radiative cooling, Composite film, Micro/nanoengineering, Structural design, Energy harvesting