Electrodes with a defined mesoscopic structure

Elucidating interfacial parameters of platinum–palladium bulk alloy single crystals

“…One This journal is © The Royal Society of Chemistry 2024 important feature that disappears is the sharp peak associated with the order/disorder transition for the sulfate adlayer on Pt(111) at 0.5 V. Scanning tunneling microscopy (STM) studies have revealed that sulfate forms an ordered adlayer with a (O7 × O3)R19.1°on several fcc (111) facets. [49][50][51][52][53][54] The phase transition from the disordered to the ordered structure is marked by the presence of sharp spikes, as those observed at the completion of the adsorption process on Pt(111), 49 Au(111), 50,51 and Pd(111). 52 The initial adsorption process leads to the formation of very small, ordered domains, which grow progressively as the adsorption proceeds.…”

Structure of the Electrochemical Interface: Ag(hkl) in an Alkaline Electrolyte

“…1,3,4 As in the ultra-high vacuum (UHV) environment, 3,5 the extraction of structural information, such as surface coverage, surface roughness, and layer spacings (both adsorbate−substrate distances and the expansion/ contraction of the substrate surface atoms themselves), relies on measurement of the crystal truncation rods (CTRs) that arise from the termination of the bulk crystal lattice. 6 If surface structures are formed that have a different symmetry to the underlying bulk crystal, for example, the surface reconstructions exhibited by the low-index Au(hkl) surfaces, 7 then they give rise to additional X-ray scattering features that can give precise structural information. 8,9 In terms of ordering on the liquid side of the interface, measurement and modeling of the specular CTR is one of the few methods that can probe the entire interface structure.…”

“…Surface X-ray diffraction (SXRD) utilizing synchrotron X-ray radiation has been prominent in the study of single-crystal metal surfaces in the electrochemical environment and has been particularly successful in identifying structural changes on the metal side of the interface. ,, As in the ultra-high vacuum (UHV) environment, , the extraction of structural information, such as surface coverage, surface roughness, and layer spacings (both adsorbate–substrate distances and the expansion/contraction of the substrate surface atoms themselves), relies on measurement of the crystal truncation rods (CTRs) that arise from the termination of the bulk crystal lattice . If surface structures are formed that have a different symmetry to the underlying bulk crystal, for example, the surface reconstructions exhibited by the low-index Au( hkl ) surfaces, then they give rise to additional X-ray scattering features that can give precise structural information. , In terms of ordering on the liquid side of the interface, measurement and modeling of the specular CTR is one of the few methods that can probe the entire interface structure. This has been elegantly demonstrated in the studies of water and cation ordering on mineral surfaces. − The classical electrical double layer model of the interface defines an inner Helmholtz plane, consisting of specifically adsorbed ions and an outer Helmholtz plane, defined by the closest approach of hydrated ions that are not directly bonded to the electrode surface .…”