6533b857fe1ef96bd12b46f2
RESEARCH PRODUCT
Effect of the Al/Si atomic ratio on surface and structural properties of sol-gel prepared aluminosilicates
V. La ParolaAnna Maria VeneziaGiulio DeganelloSalvatore Scirèsubject
Chemistrytechnology industry and agricultureAnalytical chemistryInfrared spectroscopyCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsAmorphous solidInorganic ChemistryAdsorptionX-ray photoelectron spectroscopyAluminosilicateMaterials ChemistryCeramics and CompositesAtomic ratioPhysical and Theoretical ChemistrySpectroscopySol-geldescription
Abstract A series of aluminosilicates with an Al/Si ratio ranging from 0 to ∞ (0 for pure silica and ∞ for pure alumina) was prepared by sol–gel process and characterized by surface and structure techniques. Aluminum tri sec butoxide and tetramethylorthosilicate were used as precursors for the sol–gel synthesis. The acidic properties of the oxides were studied by determination of the zero point charges, through mass titration method, and, for selected samples, by FT-IR spectroscopy of adsorbed pyridine used as a probe for both Bronsted and Lewis acidity. A dependence of the acidity on the Al/Si atomic ratio was found. According to the X-ray diffraction patterns, all the oxides have an amorphous structure except pure alumina exhibiting a γ -alumina pattern. The surface areas of the mixed oxides increase with increasing amount of alumina and are higher as compared to the individual oxides. The surface elemental distribution and electronic properties were investigated by X-ray photoelectron spectroscopy. According to the results, good agreement between the surface Al/Si atomic ratio and the analytical ratio is obtained.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2003-09-01 |