Stability of underpotentially deposited Ag layers on a Au(111) surface studied by surface X-ray scattering

Abstract

Stability of underpotentially deposited (upd) Ag layers on Au(111) surface was investigated by surface X-ray scattering (SXS). While the complete pseudomorphic Ag bilayer on Au(111) surface obtained by upd at 10 mV (vs. Ag/Ag + ) was maintained its structure even after the circuit was disconnected and the surface was exposed to ambient atmosphere, the pseudomorphic Ag monolayer obtained by upd at 50 mV was converted to a partial bilayer with the coverage of 0.66 ML and 0.46 ML for the 1st and 2nd layer, respectively. These results show that Ag bilayer is structurally more stable than Ag monolayer on Au(111) and Ag atoms of the upd monolayer move around on the Au(111) surface without potential control.

Resonance surface X-ray scattering technique to determine the structure of electrodeposited Pt ultrathin layers on Au(111) surface

“…A Au(1 1 1) single crystal disk (diameter: 10 mm, thickness: 5 mm) was purchased from the Surface Preparation Laboratory (The Netherlands) and used after the previously described pretreatments [30,35,42]. Pt wire and Pt foil were purchased from Nilaco.…”

“…We have already carried out the structural investigation of underpotentially deposited (UPD) Pd ultrathin films on Au(1 1 1) and Au(1 0 0) using in situ STM and SXS techniques and discussed the relationship between the interfacial structure and the electrochemical properties [3,[31][32][33]. We have also studied the structure [34] and stability [35] of a UPD Ag ultrathin layer on a Au(1 1 1) surface using the in situ SXS technique.…”

“…The SXS technique is ideal to determine the structure of the metal deposits with atomic precision as mentioned above, but since the atomic number and, therefore, the scattering parameters of Pt are too close to those of Au, the interfacial structure of the Pt layer on the Au substrate cannot be precisely determined from the (0 0) rod data obtained using the incident X-ray energy of 11.271 keV, which is usually used in our SXS studies [30][31][32][33][34][35][36][37].…”

Monolayers of Biphenyl-3,4′,5-tricarboxylic Acid Formed on Cu and Ag from Solution

“…[56][57][58] For Cu UPD, an incommensurate "(5×5)" Cu structure is formed by immersing Au/mica in 25 mM CuSO 4 + 5 mM KCl (aq) and applying a potential of 200 mV (vs. Cu/Cu 2+ ) for 1 minute. [59][60][61] For SAM formation on Ag, the substrate was immersed in a 0.5 mM solution of surfactant molecule for 1 hour at 65°C.…”

Step-by-step Investigation of Atomically Flattening Processes of Au(111) Single Crystal Surfaces

“…Therefore, the surface should be mechanically polished and used in a meniscus mode for the electrochemical measurements. Single crystals can be commercially available and there are some reports using the commercially available Au(111) single crystal disks as electrodes, [9][10][11][12] or as a substrate for the SAMs during the electrochemical measurements. 13,14 However, there are few detailed reports about the fundamental preparation methods of atomically flat Au(111) single crystal surfaces.…”