Urea, one of the simplest organic molecules containing carbon, nitrogen, and oxygen, is a key compound that connects chemistry and life. It is also one of the most important industrial chemicals, mainly used as fertilizer. Urea production usually relies on the direct reaction between ammonia and carbon dioxide under harsh conditions of high temperature and pressure. Using a combination of single-droplet experiments with quantum chemical modelling, Azizbaig Mohajer et al. detected spontaneous urea formation from these chemicals at the gas-liquid interface of aqueous aerosol droplets under ambient conditions (i.e. non-energetic conditions and without additional catalysts) enabled by chemical gradients across the surface of aqueous droplets. These findings have implications for various scientific disciplines. —Yury Suleymanov

source: https://www.science.org/doi/10.1126/science.adv2362