Determination of Surface Intrinsic Resilience against Bubble Coverage Using Localized Electrochemical Impedance Spectroscopy Time Domain Information

Bubble coverage on electrode surfaces presents challenges for the wide application of water electrolysis technology. Earlier experimental studies on superaerophobic electrode surfaces indicated that surface roughness of microscale morphologies can greatly increase the surface's resilience against bubble coverage at high current densities. Localized electrochemical impedance spectroscopy (LEIS) is used in this paper to assess this surface conductance under bubbles. The local impedance of the bubbleshielded area and the contour around the bubble were investigated on polished nickel and dynamic hydrogen bubble templating (DHBT) nickel surfaces with different porosities and pore distributions. This study demonstrated that porosity could reduce the resistivity caused by bubble coverage, and an evenly distributed porous surface is more resilient to bubble coverage.