Underpotential deposition of Cu on Au(111) in sulfate-containing electrolytes: A theoretical and experimental study

Abstract

We study the underpotential deposition of Cu on single-crystal Au(111) electrodes in sulfate-containing electrolytes by a combination of computational statistical-mechanics based lattice-gas modeling and experiments. The experimental methods are in situ cyclic voltammetry and coulometry and ex situ Auger electron spectroscopy and low-energy electron diffraction. The experimentally obtained voltammetric current and charge densities and adsorbate coverages are compared with the predictions of a two-component lattice-gas

Simulated Dynamics of Underpotential Deposition of Cu with Sulfate on Au(111)

“…[2]. Strengthening the attractive next-nearest neighbor copper-copper interaction, Φ (2) CC , was required to make the phase transition between the copper monolayer and the mixed phase (peaks B and B ′ in Fig. 1) first order and produce current transients for this transition in qualitative agreement with experiments (described in Sec.…”

“…Changes in the sulfate-sulfate interactions removed from the ground-state diagram three experimentally unobserved low-temperature phases which were overlooked in Ref. [2]. Strengthening the attractive next-nearest neighbor copper-copper interaction, Φ (2) CC , was required to make the phase transition between the copper monolayer and the mixed phase (peaks B and B ′ in Fig.…”

“…See, for example, the review of the experimental literature in Ref. [2]. For this system cyclic voltammograms, like the one shown in Fig.…”

Photoinduced Thermal Copper Reduction onto Gold Nanocrystals under Potentiostatic Control

“…Underpotential deposition of copper on gold is known to occur at potentials shifted 100-200 mV from the cathodic peak potential. 25,26 We observe an underpotential deposition peak at about -0.254 V and an increasing reduction wave at -0.400 V and below. This is consistent with the calculated Cu 2+ on Cu formal redox potential of -0.446 V vs Au wire (see Supporting Information).…”

Structure transitions between copper-sulphate and copper-chloride UPD phases on Au(111)

“…[28][29][30][31][32] The various adlayer structures were characterized by electron diffraction, 33,34 X-ray techniques, 24,29,[35][36][37][38][39][40] infrared absorption 26,[40][41][42][43] and Auger electron 44 spectroscopies as well as by electrochemical STM [45][46][47][48][49][50][51][52][53][54] and atomic force microscopy (AFM). 55,56 The experimental studies are complemented by theoretical modelling employing statistical mechanics, Monte Carlo simulations, density functional and/or molecular dynamics approaches.…”