SPring-8, the large synchrotron radiation facility

Date: 15:00 February 28, 2007

Place: SPring-8 HOUKOUKAN

Speaker: Dr. Frank Renner

Affiliate: National Institute of Advanced Industrial Science and Technologya (AIST)

Title: In-situ x-ray diffraction studies of electrochemical interfaces: A new portable UHV chamber

Abstract:
 The crystalline structure of matter has been revealed using X-ray diffraction and X-rays are used for materials science ever since. Modern synchrotron radiation sources provide extremely intensive X-ray beams and probing of surfaces and interfaces became possible. The relatively weak absorption of X-ray photons makes them highly suitable for revealing atomic-scale structural information of buried interfaces, in-situ and non-destructively. I will present recent progress of studies of electrochemical solid-electrolyte interfaces. With a Cu-Au single-crystalline model system we recently addressed the potential region close to the so-called critical potential, where passivation breaks down and the formation of thick
nanoporous layers sets in. The epitaxial orientation of the produced overlayers was observed to change in this potential regime. Furthermore, I will report a new portable and UHV-compatible X-ray diffraction chamber and first results of initial dealloying of a Cu-Pd crystal and on Cu electro-deposition on UHV-prepared GaAs(001). The new UHV-compatible in-situ chamber is opening the way for using more reactive systems in electrochemical surface-science-type diffraction studies.

Organizer: MIZUKI (PHS 3902)

Contact: S. Sakaguchi or N. Kasahara, SPring-8 Seminar Secretariat
 phone +81-(0)791-58-0839 / FAX +81-(0)791-58-0988
 e-mail: spring8_seminar@spring8.or.jp