Hersbach Thomas J P, Garcia-Esparza Angel T, Hanselman Selwyn, Paredes Mellone Oscar A, Hoogenboom Thijs, McCrum Ian T, Anastasiadou Dimitra, Feaster Jeremy T, Jaramillo Thomas F, Vinson John, Kroll Thomas, Garcia Amanda C, Krtil Petr, Sokaras Dimosthenis, Koper Marc T M
Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands.
Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
Nat Mater. 2025 Apr;24(4):574-580. doi: 10.1038/s41563-024-02080-y. Epub 2025 Jan 22.
Cathodic corrosion is an electrochemical phenomenon that etches metals at moderately negative potentials. Although cathodic corrosion probably occurs by forming a metal-containing anion, such intermediate species have not yet been observed. Here, aiming to resolve this long-standing debate, our work provides such evidence through X-ray absorption spectroscopy. High-energy-resolution X-ray absorption near-edge structure experiments are used to characterize platinum nanoparticles during cathodic corrosion in 10 mol l NaOH. These experiments detect minute chemical changes in the Pt during corrosion that match first-principles simulations of X-ray absorption spectra of surface platinum multilayer hydrides. Thus, this work supports the existence of hydride-like platinum during cathodic corrosion. Notably, these results provide a direct observation of these species under conditions where they are highly unstable and where prominent hydrogen bubble formation interferes with most spectroscopy methods. Therefore, this work identifies the elusive intermediate that underlies cathodic corrosion.
阴极腐蚀是一种在适度负电位下蚀刻金属的电化学现象。尽管阴极腐蚀可能是通过形成含金属阴离子而发生的，但尚未观察到此类中间物种。在此，为了解决这一长期存在的争论，我们的工作通过X射线吸收光谱法提供了此类证据。利用高能分辨率X射线吸收近边结构实验来表征在10 mol·l NaOH中阴极腐蚀过程中的铂纳米颗粒。这些实验检测到腐蚀过程中铂的微小化学变化，这些变化与表面铂多层氢化物的X射线吸收光谱的第一性原理模拟相匹配。因此，这项工作支持了阴极腐蚀过程中类氢化物铂的存在。值得注意的是，这些结果提供了在这些物种高度不稳定且大量氢气泡形成干扰大多数光谱方法的条件下对它们的直接观察。因此，这项工作确定了阴极腐蚀背后难以捉摸的中间体。
