Polarographic and redox potential studies on copper(I) and copper(II) and their complexes

Dissolution of copper oxide by the ethanolamine and ammonium fluoride in aqueous solution

“…The dissolution rate of copper oxide in the 10wt% MEA, DEA and TEA was ∼50, 30 and 25 Å/min at pH 12, respectively. Ethanolamine usually complexes with copper ions and easily forms water‐soluble compound ions such as Cu(MEA) 4 2+ , Cu(DEA) 3 2+ and Cu(TEA) 2 2+ in the basic region 10–12. The precipitation of complexes between ethanolamine and copper ions on the surface would ultimately passivate the surface of copper and copper oxide at low pH, the dissolution rate of copper oxide decreases with a decrease of pH.…”

“…In this study, the role of ethanolamine and ammonium fluoride has been evaluated in the dissolution of copper oxide from the Cu interconnection process. Because ethanolamine has the useful property of forming a chelate with copper ions and readily dissolving into water, the component can be exploited to remove metal oxide layers through the formation of Cu(MEA) 4 2+ , Cu(DEA) 3 2+ and Cu(TEA) 2 2+ complexes at the high pH values 10–12. Aqueous solutions with different pH values, containing ethanolamine, ammonium fluoride, or both, were prepared to evaluate their dissolution properties for copper oxide.…”

Carbon monoxide oxidation on copper manganese oxides prepared by selective etching with ammonia

“…In this work, a series of CMO catalysts were synthesized using a selective etching technique. With the aid of ammonia, Cu species can be selectively redissolved during the precipitation process because of the large difference in the stability constants of [Cu(NH3)x] 2+ (log = 13.1) [29] and [Mn(NH3)x] 2+ (log = 1.57) [30]. The composition and morphology of the final catalysts can therefore be manipulated.…”