Electrospinning-assisted radiative cooling composite films

The rapid increase in annual cooling energy demand has a significant adverse impact on global warming. Recent research on passive radiative cooling using various materials to reduce energy use for cooling has been reported. Most previous studies focused on solar reflection and mid-infrared (IR) emission based on photonic crystal materials. In this study, wave-selective emitter coolers in the atmospheric window range were fabricated using glass bubbles (GBu) and barium sulfate (BaSO4) in polydimethylsiloxane (PDMS). Then, polyacrylonitrile (PAN) nanofibers were electrospun on the prepared coolers. The optical properties and cooling power according to the ratio of GBu and BaSO4 contained in the cooler and PAN electrospinning conditions were analyzed. Compared with the PDMS/GBu and BaSO4 cooler, the cooler with the added electrospinning layer exhibited higher reflectivity and cooling power. This study improves the performance of previously studied passive radiative cooling.