Rox Hannes, Ränke Fabian, Mädler Jonathan, Marzec Mateusz M, Sokołowski Krystian, Baumann Robert, Hamedi Homa, Yang Xuegeng, Mutschke Gerd, Urbas Leon, Lasagni Andrés Fabián, Eckert Kerstin
Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany.
Institute of Process Engineering and Environmental Technology, Technische Universität Dresden, 01062 Dresden, Germany.
ACS Appl Mater Interfaces. 2025 Feb 12;17(6):9364-9377. doi: 10.1021/acsami.4c20441. Epub 2025 Jan 30.
Laser-structuring techniques like Direct Laser Interference Patterning show great potential for optimizing electrodes for water electrolysis. Therefore, a systematic experimental study is performed to analyze the influence of the spatial period and the aspect ratio between spatial period and structure depth on the electrode performance for pure Ni electrodes. Using a statistical design of experiments approach, it is found that the spatial distance between the laser-structures is the decisive processing parameter for the improvement of the electrode performance. Thus, the electrochemically active surface area could be increased by a factor of 12 compared to a nonstructured electrode. For oxygen evolution reaction, a significantly lower onset potential and overpotential (≈ -164 mV at 100 mA cm) is found. This is explained by the superhydrophilic surface of the laser-structures and the influence of the structured surface on the bubble growth, which leads to a lower number of active nucleation sites and, simultaneously, larger detached bubbles. Combined with the fully wetted electrode surface, this results in reduced electrode blocking and thus, lower ohmic resistance.
像直接激光干涉图案化这样的激光结构化技术在优化水电解电极方面显示出巨大潜力。因此，开展了一项系统的实验研究，以分析空间周期以及空间周期与结构深度之间的纵横比对纯镍电极性能的影响。采用实验设计的统计方法发现，激光结构之间的空间距离是改善电极性能的决定性工艺参数。因此，与非结构化电极相比，电化学活性表面积可增加12倍。对于析氧反应，发现起始电位和过电位显著降低（在100 mA/cm²时约为 -164 mV）。这可通过激光结构的超亲水表面以及结构化表面对气泡生长的影响来解释，这导致活性成核位点数量减少，同时气泡脱离尺寸增大。结合电极表面完全被润湿的情况，这会减少电极阻塞，从而降低欧姆电阻。
