A study on the voltammetric behaviour of silver on electrodispersed platinum electrodes in acid solution

✍ Scribed by M.E. Martins; R.C. Salvarezza; A.J. Arvia

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 630 KB
• Volume: 36
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(91)85015-y

✦ Synopsis

The early stages of Ag electrodeposition on columnar structured Pt electrodes was investigated in acid solutions covering the underpotential deposition (upd) and overpotential deposition (opd) ranges. Results show a remarkable dependence of the Ag growth mode on the electrode roughness and potential sweep rate. At high potential sweep rates and large substrate roughness factors a 3-D to 2-D rearrangement can be detected. This process appears to be also accompanied by a Pt-Ag formation. For this type of electrode, both processes hinder the nucleation and growth of the 3-D Ag phase. Under certain conditions the complete Ag plating of the entire porous structure can be produced and the voltammetric behaviour of the system then approaches that observed for the Ag/Ag+ electrode reaction at an electrochemical thin layer cell.