Passive radiative cooling (PRC) smart windows exhibit great potential in reducing energy consumption for building cooling. High-performance PRC smart windows should possess self-adaptability, on-demand switchability and scalability. Here, we demonstrate a PRC film with self-adaptive solar transmittance and mid-infrared (MIR) emissivity, which enables a maximum PTD of 18.9 °C and a slight temperature increase of 1.1 °C at high and low temperatures, respectively, compared to that of conventional glass. Meanwhile, the solar transmittance of this PRC film can be rapidly modulated by an electric field on demand. Moreover, the superior shearing strength of the novel PRC film enables flexible and large-scale roll-to-roll processing. This work demonstrates a practical route toward smart PRC films and windows capable of delivering year-round energy savings across diverse regions.

Liquid crsytals,polymer film,Thermochromic,Electrochromic