Pore surface fractal analysis of PEG and La(III)-doped mesoporous alumina obtained by the sol-gel method
| Autor: | B Tatjana Novakovic, P Srdjan Petrovic, M Zorica Vukovic, T Vera Dondur, S Ljiljana Rozic |
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| Rok vydání: | 2010 |
| Předmět: |
Boehmite
Materials science technology industry and agriculture Activated alumina chemistry.chemical_element Mineralogy 02 engineering and technology General Chemistry Polyethylene glycol equipment and supplies 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences law.invention chemistry.chemical_compound Chemical engineering chemistry law PEG ratio Lanthanum Surface roughness Calcination 0210 nano-technology Mesoporous material |
| Zdroj: | Journal of the Serbian Chemical Society. 75:833-843 |
| ISSN: | 1820-7421 0352-5139 |
| DOI: | 10.2298/jsc090922053n |
| Popis: | Active porous alumina was prepared via a sol-gel method and subjected to thermal treatment in the temperature range 500-1200 ?C. The addition of lanthanum effectively inhibited the surface area loss of the aluminas. Fractal analysis from nitrogen adsorption isotherm was used to study the pore surface roughness of alumina samples with different chemical compositions (PEG, PEG and lanthanum) and calcinations conditions in terms of the surface fractal dimension, d. The Mahnke and M?gel (MM) model was used to determine the value of d of La(III)-doped alumina. Following the MM model, the d value of the activated aluminas increased as the calcination temperature increased from 500 to 700 ?C but decreased after calcination at 1000, 1100 and 1200 ?C. The addition of polyethylene glycol (PEG 5600) to the boehmite sol reduced the surface fractal of the activated alumina due to the heterogeneous distribution of the pores. With increasing La(III) concentration from 0.015 to 0.045 mol La(III)/mol Al(III), the d value of La-modified alumina samples decreased, indicating a smoother surface. The obtained PEG+La-doped boehmite sol can be used as a precursor dispersion for the deposition of mesoporous alumina coatings on stainless steel foil, by the spray pyrrolysis method. |
| Databáze: | OpenAIRE |
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