Electrocatalytic reactivity of Pt ad-layer modified Au(111) single crystal electrodes on reduction of oxygen


Dursun Z. , Karabiberoglu S. U. , Gelmez B., Ertas F. N.

TURKISH JOURNAL OF CHEMISTRY, cilt.35, ss.513-521, 2011 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 35 Konu: 4
  • Basım Tarihi: 2011
  • Doi Numarası: 10.3906/kim-1102-1003
  • Dergi Adı: TURKISH JOURNAL OF CHEMISTRY
  • Sayfa Sayıları: ss.513-521

Özet

Electrocatalytic reduction of oxygen at electrochemically deposited Pt ad-layer modified Au(111) electrodes was studied in an O(2)-saturated NaOH (0.1 M) solution. The results were compared with those obtained by using a polycrystalline Pt electrode and another Pt-deposited electrode prepared by replacement with Cu on bare Au(111). Linear sweep voltammetry displayed a positive shift of the oxygen reduction potential by about 0.14 V compared to the bare Au(111) electrode. This shift was about 0.06 V compared to a Pt disk electrode. Tafel slopes gradually changed between 0.06 and 0.1 V/dec, from 0.075 to -0.10 V/dec, from lower to higher current density region. The Pt ad-layer clearly served as a catalyst for oxygen reduction via 4-electron transfer. In terms of the desired shift in reduction potential and increased current density, the best electrocatalytic activity was obtained with a 30-s electrodeposited Pt ad-layer modified Au(111) electrode.