Non‐OH‐driven liquid‐phase chemistry in water microdroplets
Gaurav Nayak, Jianan Wang, Rui Li, Diana Aranzales, Selma Mededovic Thagard, Peter Bruggeman
Abstract
Abstract Water microdroplets containing organic and fluorinated compounds, such as formate, perfluorooctanoic acid (PFOA) and triflic acid, were exposed to a radiofrequency glow discharge plasma with a droplet residence time on the order of milliseconds. Triflic acid remained unaffected by any plasma condition while >75% decomposition of formate and PFOA could be achieved. In situ hydroxyl (OH)‐laser‐induced fluorescence measurements near the droplets confirmed that the conversion was independent of the OH flux to the droplet. A series of control experiments suggest that the contribution of vacuum UV photons in such decomposition of aqueous compounds can be significant for He and He + 17% Ar plasmas and can also explain unexpected decomposition trends as a function of droplet residence time in the plasma.