Data publication: Dual wetting electrode surfaces for alkaline water electrolysis

Tuning the electrode surfaces for better bubble management is a promising approach to increase the efficiency of alkaline water electrolysis. Therefore, Direct Laser Writing was used to structure Nickel electrodes with a dual wetting surface. The applied pillar-like structure combines superhydrophilic behavior and strong spreading of the liquid across the electrode with hydrophobic bubble nucleation sites. In addition, the electrochemically active surface area is increased by a factor of 9. As a result, the overpotential has been significantly reduced, while the size of the detached bubble has increased. The present data set compares three different electrodes, a non-structured reference electrode and two laser structured electrodes with different depths of the structure, at applied current densities of<strong> <em>j</em> = -20, -50 and -100 mA/cm²</strong> in terms of electrode potential, detached bubble size and number of nucleation sites. As electrolyte <strong>1 M KOH</strong> was used. All experiments were carried out under ambient conditions (<strong><em>T</em> = 293 K,<em>p</em> = 1 bar</strong>).

<strong>Description of <em>Data.zip</em>:</strong>

An overview of all performed experiments is given in the file <strong><em>Summary.csv</em></strong>. The data is analyzed as described in the corresponding journal publication <strong><em>Dual wetting electrode surfaces for alkaline water electrolysis</em></strong>. Each data set is stored in a .hdf5-file, with the relevant metadata incorporated into the attributes assigned to the groups/datasets within the .hdf5-file. The data files are structured in groups as follows:

Electrochemical Measurement Data

Galvanostatic Measurement Data
CV double-layer capacitance
LSV onset potential

Results

Detected Bubbles Sideview

<em>Sideview Raw Images (only for <strong>SH2_LS_Pil_01.hdf5</strong>)</em>

With the exception of a single comprehensive data set comprising unprocessed images (<strong>SH2_LS_Pil_01.hdf5</strong>), the remaining raw images from all performed measurements can be made available upon request.