Spraying of water microdroplets forms luminescence and causes chemical reactions in surrounding gas

Abstract

When neutral water is sprayed, oppositely charged microdroplets are formed. The close approach of oppositely charged microdroplets causes an electrical discharge and leads to luminescent emission. The light emission happens without any external voltage applied, and the electrical discharge is sufficiently energetic to excite, dissociate, or ionize surrounding neutral gas molecules. Thus, sprayed water microdroplets cause chemical reactions to occur. Similar findings to the Urey-Miller experiment were observed by spraying room temperature water microdroplets into a gas mixture containing nitrogen, methane, carbon dioxide, and ammonia, which leads to the synthesis of organic molecules containing carbon-nitrogen (C—N) bonds. These observations provide another explanation for unique reactivity at the gas-water interface, as well as a possible mechanism for making the building blocks of life on early Earth.