Although radiative cooling concepts guarantee reduction of air conditioning energy consumption by maximizing the scattering of solar radiation and dissipation of thermal radiation of a human body or building, large-scale implementation is challenging due to the need of radical adaptation in manufacturing processes, materials, and design. Here, we introduce an extremely thin layer of nanoporous microfibers without any additional materials or post-treatments. The optical and thermal effectiveness of porous fibers are presented to report a nondisruptive method of preventing the transmission of energy-intensive radiation such as ultraviolet radiation (UV) through textiles. Results show ∼1.4 °C cooling by adding 1 g/m2 (GSM) of porous fibers on a 160 GSM cotton t-shirt, and 91% of UV was prevented with 7.5 GSM of a porous fiber mat. This minimalistic additive approach would widen the scope of optical and radiative cooling research and accelerate both functional and sustainable materials research to be more accessible.
Keywords: UV protection; hierarchical structure; nanoporous fiber; scalable cooling textile.