INSITU XPS STUDY OF THE PHOTOASSISTED REDUCTION OF NOBLE-METAL CATIONS ON TIO2

被引：17

作者：

FERNANDEZ, A ^{[1
]}

GONZALEZELIPE, AR ^{[1
]}

机构：

[1] UNIV SEVILLA,DEPT QUIM INORGAN,E-41080 SEVILLE,SPAIN

来源：

APPLIED SURFACE SCIENCE | 1993年 / 69卷 / 1-4期

关键词：

D O I：

10.1016/0169-4332(93)90520-L

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

In this work we have carried out an ''in situ'' XPS analysis of the photoassisted reduction of noble-metal cations supported on titanium oxide by irradiation of Rh3+-, Pt4+-, Pd2+- and Ag+-TiO2 precursors in the presence of an i-PrOH/H2O vapour pressure. This analysis has enabled a comparison of the photoreduction rate of the different metals. It has also shown that the metal dispersion that can be obtained working at the gas/solid interface is higher than that obtained during the photoreduction of the same metals on TiO2 in an i-PrOH/H2O suspension at the liquid/solid interface. In addition, it has been observed that the reduction of a polyvalent metal cation occurs step by step, so that while the reduction of Ag+ and Pd2+ proceeds rapidly up to the metallic state, other metals like pt4+ or Rh3+ are only partially reduced up to Pt2+ or Rh+. The role of the small metallic clusters on the surface of TiO2 as traps for the photogenerated electrons has also been highlighted.

引用

页码：285 / 289

页数：5

共 12 条

[1] LIGHT-INDUCED REDUCTION OF RHODIUM(III) AND PALLADIUM(II) ON TITANIUM-DIOXIDE DISPERSIONS AND THE SELECTIVE PHOTOCHEMICAL SEPARATION AND RECOVERY OF GOLD(III), PLATINUM(IV), AND RHODIUM(III) IN CHLORIDE MEDIA [J].