4th EucheMs chemistry congress

Poster Session 2
s1260
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - Nanochemistry, Nanotechnology
P - 0 7 9 5
nAnoPArtiCLeS in two-PhASe SePArAtion
MethodS
v. vorotyntSev 1
1 Nizhny Novgorod State Technical University n.a. R.Y. Alekseev,
FTMCET department, Nizhny Novgorod, Russia
One of the most important ways to raise the degree of purity
of substances is to improve the methods of high purification for
new type of impurities. These new impurities are impurities in the
form of suspended particles of submicron size and recently named
nanoparticles [V.M. Vorotynsev Nanoparticles in two-phase
systems.- Moscow: Izvestiy.2010.-320 p].
The peculiarity of the current stage of technology
development of high-purity substances is a merging of the size of
a number of heterogeneous impurities with impurities in
molecular form. Behavior of nanoscaled particles in the two-phase
distillation and crystallization methods of separation requires new
conceptual apparatus and new technological approaches.
In this report are considered the concepts of nanoparticles
as impurities in high-purity substances, the nature and method of
its generation in gas, liquid and solid substances. Investigation of
high purification of liquids from suspended nanoparticles
including experimental determination of separation coefficient of
nanoparticles between liquid and vapor, method for determining
the content of nanoparticles, determination of its separation
coefficient, dependence of nanoparticles separation on their size
and the velocity of distillation. Also it is considered the high
purification from nanoparticles by rectification. It was given
the design of apparatus for new separation method
– termodisstillation. It was shown the application of
termoditillation method in silicon and germanium production, in
epitaxial structures production and in optical fiber raw material
production. It was considered the distribution of nanoparticles in
the phase equilibrium in the crystallization process. The
mechanism of capture of nanoparticles from melt by the growth
crystal has been proposed. It was shown the transition of
nanoparticles from melt to crystalduring the crystallization for
electrolyte and nonelectrolite solutionsIt is considered the
dependence of separation factor countercurrent crystallization
column on the fraction of recrystallized solid phase and
dependence of separation factor.
Keywords: nanoparticles; distillation; crystallization;
high-purity substances; silicon;
4 th EucheMs chemistry congress
P - 0 7 9 6
fABriCAtion of GoLd MiCro-StruCtureS viA
reACtion Between hydroxyLAMine And
ChLoroAuriC ACid
K. winKLer 1 , M. LiSzewSKA 2 , A. KAMinSKA 1 ,
t. woJCieChowSKi 3 , M. fiALKowSKi 1
1 Institute of Physical Chemistry, Department of Soft Condensed
Matter, Warsaw, Poland
2 Military University of Technology, Department of Explosive
Materials, Warsaw, Poland
3 Institute of Physics, Department SL-3, Warsaw, Poland
Reaction between chloroauric acid (HAuCl ) and
4
hydroxylamine hydrochloride (NH OH·HCl) is widely used in a
2
seed-mediated growth of gold nanoparticles. It is commonly
believed that hydroxylamine can reduce Au3+ ions to Au0 only in
the presence of metallic gold. The possibility of nucleation in the
mixture of HAuCl and NH OH·HCl has never been confirmed
4 2
experimentally and, until now, has been remaining only a
hypothesis.
Here, for the first time, we demonstrate the evidence of
nucleation in mixtures containing aqueous solutions of
chloroauric acid and hydroxylamine. Moreover, we employ this
reaction as a powerful tool in a fabrication of new metallic
nano-materials.
In our approach, gold micro-flowers (AuMFs)—metallic
particles of expanded nano-structured surface—are formed in the
bulk solution. In the process the AuMFs sediment and deposit
onto solid substrate. The method offers easy control both over the
AuMFs morphology and density of the gold coating, which is
formed as a result of the deposition of the AuMFs. Also, by
addition of halides or silver ions to the reaction mixture we can
to a great extent modify the morphology of the resulting coating.
In particular, for certain compositions of the reaction mixture, a
porous metallic film can be obtained instead of the micro-flower
coating. Both the thickness and the roughness of such films are
controllable by the mixture composition.
The metallic layers obtained with our method have been
used as efficient platforms for chemical and biological sensing
based on surface enhanced Raman spectroscopy (SERS). The
obtained platforms have been proven to be mechanically stable
and to have good SERS enhancement factors as well as excellent
repeatability.
Keywords: nanostructures; microporous materials; surface
plasmon resonance;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc