Institute of Engineering Thermodynamics, German Aerospace Center, Pfaffenwaldring 38-40, Stuttgart, 70569, Germany.
Hydrogenics Corporation, 220 Admiral Boulevard, Mississauga, ON L5T 2N6, Canada.
Sci Rep. 2017 Mar 15;7:44035. doi: 10.1038/srep44035.
Cost reduction and high efficiency are the mayor challenges for sustainable H production via proton exchange membrane (PEM) electrolysis. Titanium-based components such as bipolar plates (BPP) have the largest contribution to the capital cost. This work proposes the use of stainless steel BPPs coated with Nb and Ti by magnetron sputtering physical vapor deposition (PVD) and vacuum plasma spraying (VPS), respectively. The physical properties of the coatings are thoroughly characterized by scanning electron, atomic force microscopies (SEM, AFM); and X-ray diffraction, photoelectron spectroscopies (XRD, XPS). The Ti coating (50 μm) protects the stainless steel substrate against corrosion, while a 50-fold thinner layer of Nb decreases the contact resistance by almost one order of magnitude. The Nb/Ti-coated stainless steel bipolar BPPs endure the harsh environment of the anode for more than 1000 h of operation under nominal conditions, showing a potential use in PEM electrolyzers for large-scale H production from renewables.
通过质子交换膜（PEM）电解生产氢气，降低成本和提高效率是主要挑战。钛基组件（如双极板（BPP））对资本成本的贡献最大。本工作提出分别采用磁控溅射物理气相沉积（PVD）和真空等离子喷涂（VPS）在不锈钢 BPP 上涂覆 Nb 和 Ti。通过扫描电子显微镜（SEM）、原子力显微镜（AFM）和 X 射线衍射（XRD）、光电子能谱（XPS）对涂层的物理性能进行了深入表征。Ti 涂层（50μm）可保护不锈钢基体免受腐蚀，而 50 倍薄的 Nb 层可将接触电阻降低近一个数量级。在标称条件下，Nb/Ti 涂层不锈钢双极板在阳极恶劣环境下的运行时间超过 1000 小时，表明其在 PEM 电解槽中具有大规模生产可再生能源氢气的潜力。
