Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 8, pp. 1425−1428.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
N.B. Kondrashova, I.I. Lebedeva, E.V. Saenko, V.A. Val’tsifer, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 8,
Inﬂ uence of the Temperature-Time Conditions
on the Textural and Structural Properties of Mesoporous
Silicon Dioxide Synthesized in an Ammonia-Alcohol Medium
N. B. Kondrashova, I. I. Lebedeva, E. V. Saenko, and V. A. Val’tsifer
Institute of Technical Chemistry, Russian Academy of Sciences, Ural Branch, Perm, Russia
Received March 23, 2010
Abstract—The conditions for the formation of mesostructural silica materials (MSMs) in the ammonia-alcohol
media were determined. Mesoporous silicon dioxide was synthesized by the template liquid-phase condensation
method at high concentrations of the surfactant. The effect exerted by temperature and time of the synthesis,
autoclaving, and by organosilane additive [(trimethylsiloxy)silane] used in synthesis on the structural and textural
properties of the mesoporous material was determined. The temperature-time conditions for the preparation of
mesostructured silicon dioxide were optimized.
In recent years, the area associated with the synthesis
of mesoporous oxides and metal composites on their
basis has been developed extensively in the chemistry of
porous materials. The speciﬁ c properties of mesoporous
oxides open great opportunity for creating new effective
catalysts, sensors, and biologically active preparations
for use in industry, medicine, and agriculture.
Advances in research and use of oxides with nanosized
particles largely depend on the methods of synthesis. In this
case, one of the major problems is the synthesis of nanoma-
terials with particles of controllable size, narrow pore-size
distribution, stable structure, prolonged sorption capacity,
and high catalytic activity preserved for a long time. The
reactivity of mesoporous oxide materials is due to their
high speciﬁ c surface area, considerable pore volume, and
due to formation of surface bonds with adsorbing particles.
In this study, the conditions of the synthesis of or-
ganized mesoporous silicon dioxide with a developed
texture in the ammonia-alcohol medium were determined.
The optimal ratio of components in synthesis of
mesoporous silicon dioxide has been determined
previously [1, 2]. Tetraethylorthosilicate (TEOS) was
a source of silicon, hexadecyltrimethylammonium bro-
mide (CTAB) was a template, and tris(trimethylsiloxy)
silane, a modiﬁ er. The material was synthesized by the
following method: to a water–alcohol mixture (mass
ratio 3 : 1), 12 ml of 25% of aqueous ammonia was
added. Then, 8 g of CTAB was added and dissolved
upon agitation with a magnetic stirrer. After that, 11 ml
of tris(trimethylsiloxy)silane and 0.44 ml of TEOS were
slowly added, and the mixture was agitated for 30 min
to form a gel. The gel obtained was divided onto two
portions. One portion was placed into a ﬂ uoroplastic
autoclave and another one, into a covered glass vessel.
The samples were kept for 3 h at different temperatures.
Above 110°С, the samples were synthesized solely by
hydrothermal treatment (HTT) in autoclaves to avoid
fast evaporation of liquid phase. After the HTT was
complete, the precipitates were ﬁ ltered off, washed with
distilled water, and dried at 70–80°С. Then, the samples
were calcined at 650°С for 5 h to complete removal
of surfactant. The molal ratios of components were:
1 ТEOS : 0.44 CTAB : 0.03 TRIS : 3.5 NH
O : 10 EtOH.The structure of the samples was studied
by the X-ray phase analysis [Shimadzu XRD-7000 dif-