Reconstruction, electrode/solution interface

X-ray surface diffraction has been applied in situ to study several processes at the electrode solution interface [13, 14]. An important phenomenon in electrochemistry at Au is surface reconstruction in which a monolayer of atoms on the surface of a single crystal acquires a different arrangement from that of the... 

Apart from chemisorption, the state of reconstruction of a surface may be affected by an electric potential across the surface/ solution interface in an electrochemical system [28]. It was found that at electrode potentials positive to the potential of zero charge, the reconstruction is lifted and the surface changes to the bulk-truncated structure. Thus, the hex structure of a Au(l 00) electrode is lifted in 0.01 M HCIO4 solution at E> 0.60 V versus saturated calomel electrode, SCE, but already at E > 0.27 V versus SCE in 0.01 M H2SO4 solution, indicating the additional role of specific adsorption. These findings could recently be surprisingly well reproduced theoretically by a combination of DFT and thermodynamic considerations [30]. 

Fundamentals. A beam of monochromatic light is polarized and split into two beams. One beam passes an optical medium, e.g. the electrolyte solution in an electrochemical cell close to the solution/electrode interface. After passage it interferes with the other beam for a review of two-beam interferometry see [915, 916]. This technique was limited both with respect to spatial resolution and sensitivity for further details, see [917]. Temporal or spatial modulation of the reference beam enabled the use of very thin cells (i.e. the sensitivity was increased) and the two-dimensional reconstruction of concentration maps. 

---