Ishihara Tomoko, Tokushima Takashi, Horikawa Yuka, Kato Masaru, Yagi Ichizo
Soft X-ray Spectroscopy Instrumentation Unit, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
Faculty of Environmental Earth Science, Hokkaido University, N10W5, Kita-ku, Sapporo, Hokkaido 060-0810, Japan.
Rev Sci Instrum. 2017 Oct;88(10):104101. doi: 10.1063/1.4997820.
We developed a spectro-electrochemical cell for X-ray absorption and X-ray emission spectroscopy, which are element-specific methods to study local electronic structures in the soft X-ray region. In the usual electrochemical measurement setup, the electrode is placed in solution, and the surface/interface region of the electrode is not normally accessible by soft X-rays that have low penetration depth in liquids. To realize soft X-ray observation of electrochemical reactions, a 15-nm-thick Pt layer was deposited on a 150-nm-thick film window with an adhesive 3-nm-thick Ti layer for use as both the working electrode and the separator window between vacuum and a sample liquid under atmospheric pressure. The designed three-electrode electrochemical cell consists of a Pt film on a SiC window, a platinized Pt wire, and a commercial Ag|AgCl electrode as the working, counter, and reference electrodes, respectively. The functionality of the cell was tested by cyclic voltammetry and X-ray absorption and emission spectroscopy. As a demonstration, the electroplating of Pb on the Pt/SiC membrane window was measured by X-ray absorption and real-time monitoring of fluorescence intensity at the O 1s excitation.
我们开发了一种用于X射线吸收和X射线发射光谱的光谱电化学池，这两种方法是用于研究软X射线区域局部电子结构的元素特异性方法。在常规的电化学测量装置中，电极置于溶液中，而电极的表面/界面区域通常无法被在液体中穿透深度较低的软X射线所探测。为了实现对电化学反应的软X射线观测，在一个150纳米厚的薄膜窗口上沉积了一层15纳米厚的铂层，并带有一层3纳米厚的用于粘合的钛层，该窗口既用作工作电极，又用作大气压下真空与样品液体之间的分隔窗口。所设计的三电极电化学池由位于碳化硅窗口上的铂膜、镀铂铂丝以及一个商用Ag|AgCl电极分别作为工作电极、对电极和参比电极组成。通过循环伏安法以及X射线吸收和发射光谱对该电池的功能进行了测试。作为演示，通过X射线吸收以及在O 1s激发下对荧光强度的实时监测，测量了在Pt/SiC膜窗口上电镀铅的过程。
