Cost‐Effective Bilayer Radiative Cooling Paint via a Porous P(VDF‐HFP) Top Layer

Abstract Global warming has led to an increasing demand for cooling solutions, but traditional cooling technologies consume more electricity and increase carbon emissions. Radiative cooling has emerged as a promising alternative, offering sustainable cooling without electricity consumption. Over the past decade, various material designs have demonstrated radiative cooling performance. Particularly, fluoropolymer‐based radiative cooling paints stand out as a practical solution, offering ease of application and scalability. However, its cost is ≈5 times of conventional acrylic paints. By understanding the dependence of reflectance on light wavelength, this study proposes a cost‐effective bilayer polymer design with attractive cooling performance. The top porous P(VDF‐HFP) layer is effective enough to reflect UV and blue light in the solar spectrum and enhance solar stability while reducing the material usage by ≈70%, and the bottom commercial acrylic latex paint reflects the rest of the solar spectrum. This bilayer paint synergistically exhibits relatively high solar reflectance (≈0.9), moderate material cost (≈$1.3 m ⁻² ), and excellent UV durability (11 years equivalent). This innovative design achieves a balance between optical performance and economic efficiency, making it a viable candidate for real‐world massive implementation of radiative cooling solutions across various applications.