Bubble size distribution and electrode coverage at porous nickel electrodes in a novel 3-electrode flow-through cell

Autor: Rox, Hannes, Bashkatov, Aleksandr, Yang, Xuegeng, Loos, Stefan, Mutschke, Gerd, Gerbeth, Gunter, Eckert, Kerstin
Rok vydání: 2022
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1016/j.ijhydene.2022.10.165
Popis: A novel 3-electrode cell type is introduced to run parametrical studies of H$_2$ evolution in an alkaline electrolyte on porous electrodes. Electrochemical methods combined with a high-speed optical measurement system are applied simultaneously to characterize the electrodes and the bubble dynamics in terms of bubble size distribution and coverage of the working electrode. Three different cathodes made of expanded nickel are investigated at applied current densities of |j| = 10 to 200 mA cm$^{-2}$ without forced flow and at a flow rate of 5 ml min$^{-1}$. The applied current density is found to significantly influence both the size of detached bubbles and the surface coverage of the working electrode. The forced flow through the cathodes is found to strongly reduce the bubble size up to current densities of about 100 mA cm$^{-2}$, whereas the initial transient until the cathode surface is completely covered by bubbles is only marginally affected by the flow-through.
Comment: Accepted in International Journal of Hydrogen Energy, 20 pages, 14 figures
Databáze: arXiv