A biobased aerogel for radiative cooling

As climate change heats things up, air conditioners strain to keep us cool. In response, researchers across the globe are designing superreflective materials capable of passively cooling spaces by reflecting heat away from buildings . Now, a team from Sichuan University has used gelatin and DNA from salmon sperm to create a new, ecofriendly aerogel for radiative cooling ( Science 2024, DOI: 10.1126/science.adn5694 ). The team chose DNA as the base for their aerogel for a few reasons, writes lead author Jian-Wen Ma in an email. Not only is the biomolecule abundantly available and readily compostable, but it also offers a plethora of hydrogen-bonding sites along its length. When the DNA is combined with gelatin and then freeze-dried to create an aerogel, these sites form a cross-linked network of dynamic hydrogen bonds between the gelatin and DNA, Ma says. It's this network that allows pieces of the aerogel to easily