화학공학소재연구정보센터
Electrochimica Acta, Vol.51, No.11, 2215-2220, 2006
Anodic oxidation of Co(II) complexes with amines on a rotating Au electrode: Ligand effects in relation to the application for autocatalytic metal deposition
For the comparison of the electrochemical activity of Co(II)-amine complexes, the electrochemical response of an Au rotating disk electrode in alkaline Co(II)-glycine solutions to six amines: ethylenediamine (en), propane-1,2-diamine (pn-1,2), propane-1,3-diamine (pn-1,3), cyclohexane-1,2-diamine (chn), butane-1,4-diamine (bn), diethylenetriamine (dien), was studied. Addition of amines tested (except for bn) in mM levels shifts the open-circuit potential to more negative values by up to 0.5 V and enhances dramatically the anodic Co(II) oxidation current, as a result of Co(II) complex transformation into more stable and electrochemically active Co(II)-amine species. The effect of amines on the open-circuit potential changes in the line: then similar to en > pn-1,2 similar to chn > pn-1,3 >> bn, and on the anodic current in the sequence: then similar to en > pn-1,2 > chn > pn-1,3 >> bn. The procedure described helps to select ligands for Co(II) complexes used as reducing agents in electroless plating solutions. The amines of high electrochemical response: dien, en, pn-1,2, and possibly, chn, are suitable for electroless copper deposition, pn-1,3 (a lower response), for electroless silver deposition, and bn (no response), not suitable for electroless plating solutions. (c) 2005 Elsevier Ltd. All rights reserved.