both absorption and photoluminescence at near-ultraviolet and blue visible spectral range, which could aid in
the creation of new lasers and emitters.
The glassy smectic nanocomposites
with CdSe NPs possess nonlinear optical properties. 3 Our investigations of
the thermal-optical nonlinearity show
the high magnitude of the nonlinear
refractive index n2 = 1. 9∙ 10–2 esu. Large
values of the nonlinear optical coefficient are a result of local heating due
to the enormous oscillator strength of
the exciton transitions in CdSe NPs
and following thermal dissipation.
Large values of optical nonlinearity
coefficient and fast response time
(approximately 2. 9 ms), together with
the excellent photo- and thermostability of nanocomposites, make them
potentially suitable in optical processing applications.
Researchers have been intensively investigating the structural and optical
properties of cadmium alkanoate nanocomposites with cadmium sulfide (CdS) and
cadmium selenide (CdSe) nanoparticles
(NPs). Nanocomposites with NPs are used
for a variety of research purposes and practical applications, such as lasers, amplifiers,
optical limiters and solar cells.
Template-controlled synthesis of nano-crystals is a very promising technique for
creating NPs with small size dispersion
and shape uniformity. In such a system,
the particles provide optical properties
while the template matrix stabilizes the
particle size during growth. The ionic
liquid crystals (ILC) of metal alkanoates
act as an attractive template for the synthesis and stabilization of semiconductor or
metal NPs. 1
T. Mirnaya's research group chemically synthesized semiconductor NPs
of CdS and CdSe in a thermotropic ILC
phase of cadmium alkanoates that possess
smectic A ordering in the temperature
range of 100 °C – 200 °C. 1–2 Anisotropic
glassy nanocomposites were obtained
after rapidly cooling the thermotropic ILC
nanocomposites to room temperature.
NP size and shape is dependent on
synthesis conditions. NP size dispersion
is very small. NP size and the presence of
a layered glassy nanocomposite structure
were determined with an X-ray scattering
technique. We used transmission electron
microscopy to estimate the NP shapes and
their small dispersion by size. The CdS NPs
in the cadmium octanoate had a spherical
shape, while the CdSe NPs achieved a
quasi-2-D platelet shape.
We found that the glassy smectic
nanocomposites with CdS NPs exhibit
We used a small-angle X-ray scattering technique to confirm the layered
structure of the glassy nanocomposites and determine the NP size.
S. Bugaichuk, A. Lyashchova, D. Fedorenko,
A. Tolochko and
Institute of Physics,
T. Mirnaya and V. Asaula
V. Vernadsky Institute of
General and Inorganic
Chemistry, Kiev, Ukraine
of Kiev, Ukraine
1. T. A. Mirnaya and S. V.
Volkov. Green Industrial
Applications of Ionic Liquids, R.D. Rogers, K.R.
Seddon and S.V. Volkov,
eds. Kluwer Academic
2. G. Klimusheva et al. Liq.
Cryst. 40, 980 (2013).
3. A. Lyashchova et al. Liq.
Cryst. 40, 1377 (2013).
Metal-Alkanoate Composites with
0 1 2 3 4 5 6 7
Diffraction angle, 2u (degrees)
D~ 2–4 nm
dSm= 1.85 nm