Copper, underpotential deposition adsorption

On the Pd(lll) single crystal, iodide adsorption leads the ( /3 x y/3) R30° I superlattice at potentials lower than 0.80 V at pH =10, whereas on Pd(100), a c(2 x 2) I superlattice is found [111]. Copper underpotential deposition on noble metals is a relatively slow process, and the electrochemical response is strongly dependent on the potentiodynamic perturbation, because of... 

Copper electrodeposition on Au(111) Copper is an interesting metal and has been widely investigated in electrodeposition studies from aqueous solutions. There are numerous publications in the literature on this topic. Furthermore, technical processes to produce Cu interconnects on microchips have been established in aqueous solutions. In general, the quality of the deposits is strongly influenced by the bath composition. On the nanometer scale, one finds different superstmctures in the underpotential deposition regime if different counter-ions are used in the solutions. A co-adsorption between the metal atoms and the anions has been reported. In the underpotential regime, before the bulk deposition begins, one Cu mono-layer forms on Au(lll) [66]. 

We have previously employed such techniques in the study of iodide adsorption onto Pt(lll) electrodes (2 5 > as well as in the in-situ structural characterization of underpotentially deposited copper and silver on Au(lll) electrodes. (23.)... 

The most remarkable feature is that the peaks representing copper underpotential adsorption disappear in the presence of iodide in solution when its concentration reaches values higher than 0.5 mM, but the anodic peak is still present due to the bulk deposition of copper. However, the... 

This rather simple experiment demonstrates quite clearly the poisoning of the oxygen reduction process by copper. Incidentally, Cu(II) is a rather common impurity in distilled water and mineral acids, and this experiment demonstrates that underpotential deposition of a monolayer of copper from solutions containing as little as 1 ppm Cu can drastically affect the behavior of a platinum electrode. Adsorption of small amounts of other impurities (i.e., organic molecules) can also have an effect on solid-electrode behavior. Thus, electrochemical experiments often require making great efforts to establish and maintain solution purity. 

Nishihara C and Nozoye H 1995 Influence of underpotential deposition of copper with submonolayer coverage on hydrogen adsorption at the stepped surfaces Pt(955), Pt(322) and Pt(544) in sulfuric acid solution J. Electroanal. Chem. 396139-42... 

Second harmonic generation has also been used to study the semiconductor/ solution interface during the deposition of gold on Si(lll) [777]. In a setup combining SHG and the electrochemical quartz crystal microbalance (EQCM), the underpotential deposition of copper on a polycrystalline gold surface has been studied a decrease of the SHG signal by 60% upon formation of the upd-layer was found [778]. A study of the electrochemical liquid/liquid interface between two immiscible solutions where adsorption of surfactants occurred has been reported [779]. 

The Effects of Bromide Adsorption on the Underpotential Deposition of Copper at the Pt(lll)—Solution Interface... 

Electrochemical Active Surface Area (ESCA) of Pt-based catalysts through the hydrogen adsorption/desorption peak area, CO stripping, and underpotential deposition of copper (Cu-UPD) methods. 

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