Experimental detection of liquid-phase OH radical decay originating from atmospheric-pressure plasma exposure

Breaking-through methods for experimental observation on short-lived reactive species in the liquid phase, generated at the interface of atmospheric-pressure plasmas (APPs), can contribute greatly to an understanding of the reaction processes. A newly developed high-speed liquid flow interface in helium plasma transports APP-generated liquid-phase OH radical ( OH) by advection, enabling observation of rapid APPgenerated OH decay within approximately 0.5 ms for the first time, to our best knowledge. This experimental detection and the deduced quantification of the rapid OH decay suggests a surface localization of OH, and thus can be an important finding to characterize the inhomogeneous OH distribution.