Electrocavitation in nanofluidics: unique phenomenon and fundamental platform

In this paper, we will highlight one phenomenon unique to nanofluidics: electrocavitation. Electrocavitation is defined as cavitation induced by electric fields. Cavitation in general occurs in a liquid when it is subjected to a pressure below its vapor pressure, where the liquid can break apart and form a cavity (bubble). This is frequently seen in macroscale systems, for example, rotating propeller blades on the turbines of ships or water columns in the xylem of trees. Electrocavitation in nanochannels was first reported when researchers applied electric fields within nanochannels containing electrolytes discontinuous in conductivity and found that bubbles formed within the channel. The reasons to highlight electrocavitation to both the lab-on-a-chip community and those interested in the fundamental understanding of cavitation in general are detailed below.