Visualization of self-limiting electrochemical gas generation to recover underwater superhydrophobicity

We develop a transparent superhydrophobic (SHPo) surface with an imbedded electrode to investigate the selflimiting gas recovery mechanism reported for a long-term SHPo state underwater [1]. The surface is made from two Teflon sheets by two hot-embossing steps that embed a metal strip in between. The self-initiation of electrochemical gas generation at liquid impalement and self-termination at full gas recovery of a microtrench is directly visualized. Furthermore, we develop a high-pressure chamber to study the mechanism at elevated hydrostatic pressures (up to 4 atm tested).