Dr. Lili Cai and her team at the University of Illinois have developed a new nanoporous composite material for passive cooling applications. This composite has solar reflectivity of 96.2%, infrared emissivity greater than 90%, and can generate a cooling power of 85 W/m2 to reduce subambient temperature by up to 6.1°C without any energy inputs. The material is inexpensive, easier to fabricate than state-of-the-art passive cooling materials, and can retain its properties even after thermal processing or 3D printing.