Presrnt

1. PECULIARITY OF NANOLEVEL
STRUCTURING IN SYNTHESIS OF
NOVEL FUNCTIONAL SOLIDS AND
NANOSTRUCTURED MATERIALS
V.M. Smirnov, I.P. Suzdalev
Saint-Petersburg State University,
Department of Chemistry,
Solid State Chemistry Division

2. The State of Two-Dimensional
Nanostructures on the Silica Surface
• А – with homogeneous character of distribution of
chemical composition and state, for example, monolayers
of element-oxygen groups of the same chemical
composition, l – monolayer thickness, L – layer thickness,
l1 = l2 = l3 = l4; 1– for example, Ti–O monolayers.
• B – periodic distribution of element-oxygen layers
along z axis, (L – layer thickness) consisting of the certain
quantity of monolayers, for example, according to the
scheme: 1 –Fe-O groups, 2 –Ti-O groups (a – two-layer
group, l1 = l2 , б, в – four-layer group l1 = l3 и l2 = l4 ).
• C – aperiodic distribution of element-oxygen layers
along z axis, four-layer structure l1 l2 l3 l4
• D – aperiodic distribution of atoms on the plane of
surface monolayer, top view: х –Fe-O groups, о –Ti-O
groups; а, б – different ratios of groups Fe-O and Ti-O.
• E - aperiodic distribution of “zero-dimensional"
structures on the plane of support: 1 –Si , 2 – [ Fe]

3. Energetic Diagram of Reaction with Kinetic and
Thermodynamic Control
[SiO2]m-1O1,5SiOH + Cl2 [SiO2]m-1O1,5SiCl SiCl4
A B C
1 – reaction A → B
dominates, product
B is kinetically stable;
Free Energy
2 – side reaction A → C
dominates;
3 – reaction A → B
dominates, but the
product B is kinetically
unstable and converts
rapidly into C.
Reaction coordinate

4. The Scheme of Chemical Construction of
Oxide Nanostructures by the Molecular
Layering Method
Si-OH
• O + CH3OH
• Si Si-O-CH3
monolayer
Functional groups
mixture
Solid matter
surface
a – layer of the set thickness ; b – layer of the set arrangement of
monolayers of different chemical nature; c – multicomponent monolayers

5. Stoichiometry of Interactions OH-groups of
Silica with FeClз at Temperature above 200 C
a – initial content of ОН-groups before reaction; b – Nchem/Nsurf = Fe/ОН;
c – Standardization of the sample surface 2a and 2b was carried out by thermal
treatment in oxygen at 723 K for 8 hours and then thermal vacuum treatment at
623 K for 20 hours (vacuum is 8·10-6 Pa).

6. Interactions OH-groups of Silica with FeClз

7. The Scheme of State of
Solid Chemical Compounds
3
1 – initial metal
oxide (MOn);
2
2–surface chemical
compound [MO]n-1
1
(M– O)2 Si(OH)2 ;
3–spatially divided
compound [MOn]–
[SiO2];
1 – conditional
(internal) border of
division

8. The Fragment of Structure of Solid Matter,
Consisting of the Parts of Different Chemical
Composition (Si–O and Ti–O Groups), Connected in
3 Different Ways
•1 – spatially divided compound;
• 2 – spatially divided adduct;
•3 – mechanical mixture of particles of SiO2 and TiO2 .

9. Dimensional Dependencies of the
Properties of Solid Compounds
1 – crystal lattice
1 2
parameter for
silicon
(curve 1) and
cerium dioxide
(curve 2);
2 – critical
temperature of
3
superconductivity
Tc and derivative
of critical
magnetic field for
tin layers on the
glass;
3 – tensile strength  of crystal.  – sample size.

10. Generalized View of Dependence of Properties
on Size of Chemical Matter
Subcrystal
Property
Massive
crystal a – for the solid matter;
b – change of the value of
specific Surface S depending on
Size of Solid Matter ()
b [according to V.B. Aleskovskii].
1 – size of minimal solid matter
(nanoobject);
2 – size of dispersed solid state
(micro object);
3 – massive (macroscopic) solid.

11. The State of Two-Dimensional
Nanostructures on the Silica Surface
• А – with homogeneous character of distribution of
chemical composition and state, for example, monolayers
of element-oxygen groups of the same chemical
composition, l – monolayer thickness, L – layer thickness,
l1 = l2 = l3 = l4; 1– for example, Ti–O monolayers.
• B – periodic distribution of element-oxygen layers
along z axis, (L – layer thickness) consisting of the certain
quantity of monolayers, for example, according to the
scheme: 1 –Fe-O groups, 2 –Ti-O groups (a – two-layer
group, l1 = l2 , б, в – four-layer group l1 = l3 и l2 = l4 ).
• C – aperiodic distribution of element-oxygen layers
along z axis, four-layer structure l1 l2 l3 l4
• D – aperiodic distribution of atoms on the plane of
surface monolayer, top view: х –Fe-O groups, о –Ti-O
groups; а, б – different ratios of groups Fe-O and Ti-O.
• E - aperiodic distribution of “zero-dimensional"
structures on the plane of support: 1 –Si , 2 – [ Fe]

12. ▒║–O–A–O–B–OH (sample АВ) Layered-
▒║–O–В–O–А–OH (sample ВА) inhomogeneous
structures
▒║–O–A–O–А–О–B–OH (sample 2АВ)
The activity of
two-
component
oxide
nanostructures
in catalytic gas
phase reaction
of CCl4
hydrolysis at
2400 C

13. Influence of Fe-O and Ti-O Groups Ratio in
Monolayer on the Catalytic Activity
in Photo Induced Decomposition of H2O
A – activity
A = 300 at Fe3+/Ti4+ =0.69 in monolayer
A = 1 at Fe3+/Ti4+ =0.69 in mixture Fe2O3 and TiO2
Fe2O3 and TiO2
mixture
Fe3+/Ti4+ ratio in monolayer

14. Magnetic Susceptibility of One-
Component and Two-Component
Nanostructures
n – number of element-oxygen monolayers
two-component monolayer

15. Sorption Properties of
Nanostructured Materials
The scheme of structure of
ferromagnetic
nanostructured sorbent of
uranium ions
а – sample with two monolayers of Ti-O 1 – SiO2 particle (aerosil);
groups 2 – layer of Fe3O4 (10 –15Å
b – sample with iron-oxygen monolayers thick);
and two monolayers of Ti-O groups, having 3 – layer of TiO2 (6 – 10Å
ferromagnetic properties thick).

16. Investigation of Mechanical Properties
of Composite Materials on the Basis of Iron
•*Sample 1: on the basis of
iron;
•Sample 2: with iron carbide
obtained by the addition of
carbon powder ;
•Sample 3: with titanium
carbide obtained by the
sedimentation of it from gas
phase;
• Sample 4: with ultrathin layer of titanium carbide obtained according to the
reactions 7 and 8;
• Sample 5: for the comparison disperse-reinforced material with titanium matrix and
disperse-reinforced SiC fiber.

17. Conclusion
Therefore, we can ascertain that by present
time, the scientific base is created allowing to
solve complex synthetic problems, including
construction of highly organized nanostructured
solid substances and materials.