Fig. 3: Electrolyte puddle formation at bubble-electrode interface.
a–d Backside views from underneath the electrode of the growing H2 bubble attached to the transparent planar Pt electrode. b Zooms into the bubble-electrode contact area shown by the red rectangle in (a), demonstrating the development of electrolyte puddles throughout the bubble evolution. c, d Schematic and shadowgraphs illustrating the injection of microdroplets upon coalescence events followed by their sedimentation at the contact area. The measurements were carried out at a current density of −50 A m−2 in 0.1 mol L−1 HClO4. The image recording in (a, b) and (d) was performed at frame rates of 60 Hz and 3000 Hz, respectively. For further details, we refer to Supplementary Movies 5 and 6.
