An integrated study of Pt/WO3/SiO2 catalysts for the NOCO reaction
1987; Elsevier BV; Volume: 107; Issue: 1 Linguagem: Inglês
10.1016/0021-9517(87)90277-6
ISSN1090-2694
AutoresJ.R. Regalbuto, T.H. Fleisch, E.E. Wolf,
Tópico(s)Gas Sensing Nanomaterials and Sensors
ResumoPt/WO3/SiO2 catalysts were characterized by X-ray diffraction (XRD), selective CO chemisorption, and X-ray photoelectron spectroscopy (XPS). It was found that the presence of WO3 decreased final Pt crystallite size, in part by reducing the formation of bulk PtCl2 precursor. However, CO chemisorption was suppressed; this indicated strong metal-promoter interactions. Changes in Pt electron binding energy suggest that charge transfer may also take place. A model of the surface consisting of Pt crystallites decorated by partially reduced WOx is proposed. This morphological model was supported by XRD and XPS results which revealed a surface-localized phase of partially reduced WOx (likely WO2). Decoration was also indicated in the trend of XPS PtSi ratios.
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