Short pulse laser structuring as a scalable process to produce cathodes for large alkaline water electrolyzers

This paper presents a novel scalable electrode fabrication process suitable for large alkaline water electrolysers. Laser structuring technology is applied, and a large-scale development of active Ni-based cathodes is demonstrated. The most active electrode shows an overpotential of 104 mV at a current density of 300 mA cm−2 for the hydrogen evolution reaction at the end of the accelerated durability test protocol. Large 400 × 600 mm2 electrodes have been fabricated for the first time, and the electrodes thus fabricated are compared with state-of-the-art electrodes in an industrial alkaline electrolyzer. Within the test period, the laser-structured Ni electrodes significantly outperformed the comparison electrodes. This impressively high activity is attributed to the existence of Ni oxide adjacent to the metallic Ni reaction sites. •Multi-spot laser processing used to activate cathodes for alkaline electrolysis.•Multi-spot laser processing roughens the electrode surface drastically.•HER activity is directly related to the oxygen content in the surface layer.•Electrodes were tested on lab scale as well as in an industrial electrolyzer.