Zr and Ag L-edge XANES studies of Ag nanoparticles in nanoporous Zr-Si-O thin films

ANDRINI, L.; WOLOSIUK A; ANGELOME, P; SOLER-ILLIA, GJAA; REQUEJO, FG

Activity Report / Brazilian Synchrotron Light Laboratory (1997/98) - Campinas - SP

LNLS, CNPq

Lugar: Campinas (Brasil); Año: 2008 p. 1 - 2

1518-0204

Mesoporous zirconia-silica (MZS) have been extensivelyinvestigated, for their high potential in catalysis, in particularfor creating controlled nanometric cavities with regular spatialseparation [1]. The well-known activity of silver for selectiveoxidation of hydrocarbons [2] becomes the Ag-MZS systemas a promissory model catalyst because the introduction ofsilver in the pores of MZS oxides gives highly ordered activecatalytic sites.We report the study of the modifications in the MZS oxideafter introduction of silver into their pores. According to thecrystal-field information obtained from the Zr L2,3 and AgL2,3-XANES spectra we obtained direct evidence of chargetransference between Ag nanoparticles and Zr ions in the sur-face of MSZ.