Electrospun film composed of pearl-string-like microfibers exhibiting excellent radiative cooling performance, moisture permeability and self-cleaning function

The double threat of extremely hot summer and the pandemic of Covid-19 makes it important to develop protective clothing with remarkable advantage of personal thermal management. Meanwhile, radiative coolers with strong solar reflection and atmospheric window (8–13 μm) emission can cool objects without the requirement of extra energy input. Passive daytime radiative cooling has attracted extensive attention in the field of personal thermal management. However, radiative cooling textile for protective clothing remains to be explored. In this work, electrospinning technique was applied to prepare radiative cooling flexible film for protective clothing. The prepared film is composed of microfibers with pearl-string-like structures that result in high average solar reflectance (98.1%) and high average atmospheric window emittance (94.9%). The film delivers an average temperature drop of 6.1 °C and an average radiative cooling power of 79 W m−2. The radiative cooling film has good moisture permeability and self-cleaning function. This study has opened up a promising way for the design and fabrication of protective clothing that has excellent passive daytime radiative cooling performance.