POTENTIAL-DEPENDENT SURFACE SEGREGATION IN LEAD PLUS RUTHENIUM PYROCHLORE PB2RU2O7-Y

GOKAGAC G., KENNEDY B.

JOURNAL OF ELECTROANALYTICAL CHEMISTRY, cilt.353, sa.1-2, ss.71-80, 1993 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 353 Sayı: 1-2
  • Basım Tarihi: 1993
  • Doi Numarası: 10.1016/0022-0728(93)80287-r
  • Dergi Adı: JOURNAL OF ELECTROANALYTICAL CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.71-80
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

The effect of anodic polarization on the surface composition of Pb + Ru pyrochlore Pb2Ru2O7-y in acid and acid+alcohol solutions has been studied using cyclic voltammetry, scanning electron microscopy, energy dispersive analysis and X-ray photoelectron spectroscopy. In acidic solutions the surface is observed to be unstable to oxygen evolution even at reasonably low overpotentials. Lead is found to diffuse from the pyrochlore matrix resulting in the formation of small crystallites of PbO2 on the surface of a mixed Pb + Ru oxide substrate. RuO2 does not appear to form on the surface.