The Nature and Thiknesses of Passive Films on Interface Cu/ NaOH+Alanine

Abstract

Thicknesses of films formed on the copper in alkaline solution in the presence of alanine are studied by ellipsometric method. It was found that small additives of β-alanine (10-4-10-3 mol/l) cause additional stabilization of copper passivity due to an increase in the film thickness. The adsorption kinetics of α- and β-alanine is studied. It is shown experimentally that β-alanine adsorbs on copper according to the Frumkin isotherm. By contrast, no definite type isotherm can be obtained for α-alanine due to its higher activity and ability to form soluble complexes with copper ions.

Anodic Copper Oxidation in Alkaline Mediums with α-Alanine and Asparagine Acid Additives

“…In connection with the possibility of using the aminoacids (AA) as complexing additives for solving different problems of applied electrochemistry (1)(2)(3)(4) it was carried out the cycle of investigations to discover the role of one of the most applicable monoaminocarbon acids -α-Ala and Asp -as an example of dibasic aminoacid, which has higher complexing and adsorption properties at copper electrochemical process, where copper is in active or in passive state, or undergoes local activation (LA) (5)(6)(7)(8). The analysis of experimental data has shown not simple influence of investigated aminoacids on copper anodic oxidation regularities, especially sharply revealing at metal local surface destruction conditions and significantly depending on concentration of aminoacid, anion composition and solution pH.…”