9 research outputs found
Fast Structure Determination of Electrode Surfaces for Investigating Electrochemical Dynamics Using Wavelength-Dispersive X‑ray Crystal Truncation Rod Measurements
Determining
the atomic structure across electrolyte–electrode
interfaces with a sufficient temporal resolution is crucial to understanding
how electrochemical reactions proceed. Surface X-ray diffraction is
a well-established method for determining interface structures at
the atomic scale. However, existing measurement methods are often
incapable of quantifying time-dependent structural changes during
electrochemical processes because acquiring a diffraction rod profile
sufficient for structure determination usually takes a longer time
than the rate of the structural changes. This report demonstrates
that the wavelength-dispersive method, which can acquire a range of
the diffraction rod profile at once, is capable of the time-resolved
analysis of electrochemical dynamics on a time scale of seconds and
less, using electrochemical reactions on Pt(111) electrode surface
as examples. In the case of the electrochemical oxidation of methanol,
the quantitative analysis of the transient vertical displacement of
the Pt(111) surface atomic layer gives evidence for a structural relaxation
of the CO poisoning layer during its oxidative stripping. Present
limitations and future prospects of the method are also discussed