PREPARATION OF MESOPOROUS TITANIA-SILICA AEROGELS BY CO2 SUPERCRITICAL EXTRACTION
ABSTRACT: Stable anatase is
attractive because of its notable functions for photocatalysis and
photon-electron transfer. TiO2-nanoparticles
dispersed SiO2 wet gels were prepared by hydrolysis of Ti(OC4H9n)4 and
Si(OC2H5)4 in a 2-propanol solution with acid catalyst. The solvent in the wet gels was
supercritically extracted using CO2 at 60oC and 22 Mpa in
one-step. Thermal evolution of the
microstructure of the extracted gels (aerogels) was evaluated by XRD measurements,
TEM and N2 adsorption measurements. The as-extracted aerogel with a large
specific surface area, more than 365 m2g-1, contained anatase nanoparticles,
about 5 nm in diameter. The anatase phase
was stable after calcinations at temperatures up to 1000oC, and BET
specific surface area, total pore volume and average pore diameter did not
change significantly after calcinations at temperature up to 800oC.
Author: Silvester Tursiloadi,
Dinie Mansur, Yeny Meliana and Ruslan Efendi
Journal Code: jpkimiagg070010
