Artículos de revistas
Assistant template and co-template agents in modeling mesoporous silicas and post-synthesizing organofunctionalizations
Registro en:
Journal Of Solid State Chemistry. Academic Press Inc Elsevier Science, v. 196, n. 293, n. 300, 2012.
0022-4596
WOS:000310394500043
10.1016/j.jssc.2012.05.042
Autor
Oliveira, VV
Airoldi, C
Institución
Resumen
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Mesoporous SBA-16 silicas were synthesized through a direct methodology using the template (F127) combined with co-templates (ethanol and n-butanol), with tetraethylorthosilicate as the silica source. These ordered mesoporous silica were characterized by elemental analyses, infrared spectroscopy, solid-state nuclear magnetic resonance for C-13 (CP/MAS) and Si-29 (HP/DEC) nuclei, nitrogen sorption/desorption processes, small angle X-ray analyses (SAXS) and transmission electron microscopy (TEM). SAXS and TEM results confirmed the space group Im3m and cubic 3D symmetry, typical for highly ordered SBA-16. The sorption/desorption data for SBA-16 and when functionalized gave type IV isotherms, with hysteresis loop H2. Surface areas of 836; 657 and 618 m(2) g(-1) and average pore diameters of 7.99; 8.10 and 9.85 nm, for SBA-16A, SBA-16B and SBA-16C were obtained, respectively. When functionalized the silicas presented a reduction in surface area, pore volume and pore diameter due to the pendant chains that interfere with nitrogen sorption in these measurements. The co-template ethanol favors the ordered mesopores with highest wall thicknesses. (C) 2012 Elsevier Inc. All rights reserved. 196 293 300 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)