Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 10, pp. 1725−1730.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
A.S. Blokhina, I.A. Kurzina, L.N. Chukhlomina, O.V. Vodyankina, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83,
No. 10, pp. 1585−1590.
INORGANIC SYNTHESIS AND INDUSTRIAL
Features of the Formation of Silver Nanoparticles
on the Silicon Nitride Surface
A. S. Blokhina, I. A. Kurzina, L. N. Chukhlomina, and O. V. Vodyankina
Tomsk State University, Tomsk, Russia
Tomsk Polytechnic University, Tomsk, Russia
Tomsk Scientiﬁ c Center, Siberian Division, Russian Academy of Sciences, Tomsk, Russia
Received December 24, 2009
Abstract—Special features of the formation of particles of a silver-containing catalyst phase on a silicon nitride
surface in relation to the mode of the active component deposition were studied. The inﬂ uence of a redox
medium of the catalytic reaction of the ethylene glycol selective oxidation to glyoxal on the ﬁ nal composition
and structure of silver catalysts was studied.
The use of ceramic materials like silicon nitride as
carrying agents for metallic particles makes it possible to
obtain catalytic systems stable against coal deposition and
active component caking . This fact is accounted for by
high speciﬁ c heat conductivity and physical-mechanical
properties of silicon nitride . However hydrophobic
properties of the surface of ceramic materials give rise
to speciﬁ c features of the formation of active component
metallic particles on the carrying agent. The absence of
surface hydroxyl groups radically distinguishes silicon
nitride from traditional oxide carrying agents of metallic
particles, such as aluminum and silicon oxides.
Along with the carrying agent properties, the mode
of the active component deposition (impregnation, frac-
tional chemical reduction, and deposition of complex
compounds or salts of an active component) also can
essentially affect the structure and physicochemical
properties of deposited particles. Furthermore the ac-
tion of high temperatures and reaction media can result
in chemical transformations of an active phase on the
carrying agent surface (reduction of salts-precursors), in
structural changes of the catalyst, and also in the partial
entraining of the active component caused by a weak ac-
tive phase-substrate interaction. Therefore it is timely to
determine physicochemical regularities of the formation
of metallic particles, in particular of silver particles, on
the surface of highly heat-conducting ceramic materials
in selective oxidation reactions of organic substances.
The aim of the present work was to study structural
and morphological features of silver-containing catalysts
deposited on silicon nitride in relation to the conditions
of the ethylene glycol (EG) synthesis by glyoxal (GO)
Silicon nitride prepared by a self-propagating high-
temperature synthesis (SHS) [3, 4] was used as the carry-
ing agent for silver-containing catalysts. To remove iron
admixtures, the synthesized product was subjected to the
acid enrichment. Silicon nitride containing 85 wt % of
α-phase and 15 wt % of β-phase was used in the work.
For the synthesis of catalytic systems we used the carry-
ing agent in the form of granules of the size 0.5–1 mm.
The phase composition of the carrying agent and also the
completeness of iron washout were controlled by X-ray
We used three procedures for the synthesis of catalytic
systems. The ﬁ rst procedure consisted in a fractional
silver precipitation from a silver nitrate aqueous solu-
tion by sodium borohydride: sample Ag/Si
-I (see the
table). Deposition of silver from a silver triﬂ uoroacetate