Structural Studies of the Solid-Liquid Interface - Reactions at the Noble Electrode Surface

Beane, Jack William
(2022) Structural Studies of the Solid-Liquid Interface - Reactions at the Noble Electrode Surface. PhD thesis, University of Liverpool.

[img] Text
200899598_Aug2022.pdf - Unspecified

Download (17MB) | Preview


Surface x-ray diffraction (SXRD) has been employed in the study of the electrochemical interface for a number of electrode surface structures. The technique is employed in situ to obtain detail on the atomic structure of model single crystal electrode surfaces. The potential dependence of the hexagonal reconstructions of gold surfaces (Au(001) and Au(111)) in hydroxide electrolyte solutions in the presence and absence of CO molecules were investigated by SXRD. Results indicated that the compressibility of the reconstructed surface structures depended on a build up of charge at the surface at negative electrode potentials and that, with CO, the surfaces are locked into highly compressed phases. The influence of cation species on the Au(111) surface reconstruction was also investigated, finding that the cation had an influence on the sensitivity of the surface reconstruction to the applied potential. Phosphate adsorption on Cu(111) was also investigated in situ by SXRD. Results show that a mixed copper-oxygen layer is formed, and the surface exhibits a reversible, potential dependent change in roughening. Experiments also reveal the importance of surface preparation, as different preparation methods are shown to produce very different surface morphologies. The surface structures formed during halide adsorption and Pb UPD at the Cu(001) surface were investigated by resonant SXRD. Structural characterisations of the adlayer and UPD structures on Cu(001) were carried out, before coupling surface diffraction and spectroscopic measurements to obtain detail on the charge distribution for different atoms in the surface structure. Results show that iodine exhibits similar behaviour to that previously reported for other halide ions, and for the UPD Pb structure formed on Cu(001), a potential dependent change in the charge distribution for atoms at the surface was observed between -0.34 V and -0.22 V.

Item Type: Thesis (PhD)
Divisions: Faculty of Science and Engineering > School of Physical Sciences
Depositing User: Symplectic Admin
Date Deposited: 05 Sep 2022 08:10
Last Modified: 18 Jan 2023 20:46
DOI: 10.17638/03162956
  • Lucas, Christopher
  • Grunder, Yvonne
  • Martin, David