Fabrication of Structured Nickel Electrodes With Tailored Wettability and Enhanced Electrochemical Active Surface Area for Alkaline Water Electrolysis Using Direct Laser Interference Patterning

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High‐efficiency alkaline hydrogen evolution requires electrodes with tailored surface properties that improve electrolyte accessibility and gas release. In this work, Direct Laser Interference Patterning is applied to produce periodic, line‐like microstructures on nickel electrodes. Using a picosecond pulsed laser with a wavelength λ = 1064 nm and a pulse duration of τ = 70 ps, patterns with a spatial period of 5.4 μm are fabricated on the nickel surface. The surface topography is characterized using white light interferometry and scanning electron microscopy, revealing texture depths up to 2.23 ± 0.41 µm. Wettability analysis on the laser‐treated samples exhibits a progressive transition toward superhydrophilic behavior. Additionally, electrochemical characterization by cyclic voltammetry demonstrates a significant enhancement of the electrochemically active surface area due to the increased surface roughness. These analyses are performed both under ambient conditions at 22°C and at an elevated temperature of 60°C. Compared to unstructured electrodes, the electrochemically active surface is enhanced by a factor of 4.7 at 22°C and 8.2 at 60°C. These findings highlight the potential of laser‐structured nickel electrodes for advancing scalable and efficient gas evolution reactions.