Speaker
Description
Surface X-ray diffraction (SXRD) is one of the most powerful methods that can determine the atomic structure of buried interfaces non-destructively. It is widely used to analyze the structure of solid-liquid and solid-solid interface to understanding the interface processes such as electrochemical reaction and thin film growth. A drawback of SXRD is that the measurements are often time-consuming: the data acquisition time is several tens of minutes or more even when a state of the art two-dimensional detector is used, which is in most cases longer than the relaxation time of the structural changes. Capturing the dynamical behavior of interfaces with a sufficient temporal resolution still remains challenging.
We have developed a high-speed technique which can acquire a wide range of SXRD profile at once within seconds or less [1]. The method uses an energy-dispersive convergent X-rays, instead of a conventional monochromatic collimated X-rays. The combination use of the energy-dispersive X-rays and a two-dimensional detector allows the simultaneous acquisition of a SXRD profile without moving the specimen and detector, enabling the real-time monitoring of interface processes [2, 3].
In this talk, we show the capability of the high-speed technique for capturing the atomic-scale processes at buried interfaces: structural change of Pt(111) electrode surface during electrochemical decomposition of methanol, and the atomic-scale growth process of topological insulator Bi2Se3 thin film.
References
1. T. Matsushita, T. Takahashi, T. Shirasawa, E. Arakawa, H. Toyokawa, and H. Tajiri, J. Appl. Phys. 110, 102209 (2011).
2. T. Shirasawa, W. Voegeli, E. Arakawa, T. Takahashi, and T. Matsushita, J. Phys. Chem. C 120, 29107 (2016).
3. T. Shirasawa, T. Masuda, W. Voegeli, E. Arakawa, C. Kamezawa, T. Takahashi, K. Uosaki, and T. Matsushita, J. Phys. Chem. C 121, 24726 (2017).
