4th EucheMs chemistry congress

Poster Session 2
s1213
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - Nanochemistry, Nanotechnology
P - 0 7 0 1
CMoS-CoMPAtiBLe LoCALized Growth And
inteGrAtion of SeMiConduCtinG nAnowireS
S. BArth 1 , r. JiMenez-diAz 2 , J. SAMA 2 ,
A. roMAno-rodriGuez 2
1 Vienna University of Technology, Institute of Materials
Chemistry, Vienna, Austria
2 University of Barcelona, Departament d’Electronica,
Barcelona, Spain
In recent years, one-dimensional semiconductor
nanostructures with tunable morphologies, dimensions,
crystallographic phases, and orientations have gained tremendous
attention due to their vast number of applications, including
electronics, sensing, energy harvesting, etc... Several techniques
have been successfully employed for the growth of high quality
semiconducting nanowires [1] ; however, most of the processes
using metal supported methodologies require high temperatures
of an entire substrate for an effective formation of single
crystalline nanowires.
In this study, we used micromembranes and microhotplates
for the localized growth of high quality semiconducting
nanowires, including Ge, SnO and In O , via LPCVD techniques
2 2 3
employing molecular sources. The heated areas were the range of
several hundreds of square microns allowing a site-specific
formation of nanowires. Key features of such microsystems are
extremely fast cooling and heating processes due to their low mass
and low power consumption. The growing nanowire bundles
bridge the gap between a set of interdigital electrodes located on
top of the heated membranes und thus leading to in situ contact
formation. This approach allows us to perform heating and
measuring operations independently, which is mandatory for
thermally supported devices such as metal oxide gas sensors. [2]
To the best of our knowledge, this is the first report for the growth
of these materials using such a technique. Additional advantages
include the possibility to grow various types of nanowires on the
same chip using multiple micromembranes or microhotplates and
the in situ contact formation replacing cost and time consuming
procedures. The presented data will demonstrate the enormous
potential of this approach for the fabrication of novel
nanostructure-based devices.
references:
1. S. Barth, F. Hernandez-Ramirez, J. D. Holmes, A.
Romano-Rodriguez. Prog. Mater. Sci. 2010, 55, 563.
2. S. Barth, R. Jimenez-Diaz, J. Sama, J. D. Prades, I. Gracia,
J. Santander, C. Cane, A. Romano-Rodriguez.
Chem. Commun. 2012, 48, 4734.
Keywords: Chemical vapor deposition; Nanostructures;
Nanotechnology; Sensors;
4 th EucheMs chemistry congress
P - 0 7 0 2
SyntheSiS And ChArACterizAtion of
Sio -SuPPorted fe/Co nAnoPArtiCLeS
2
S. BehnAM 1 , M. feyzi 1 , S. nAdri 1 , M. JoShAGhAni 1 ,
e. rAfiee 1
1 Razi University, Chemistry, Kermanshah, Iran
Introduction of cheap, efficient and selective catalysts for
production of fuels and heavier hydrocarbons from lighter ones
is of great challenge in refineries and petrochemical industries [1] .
Both Fe- and Co-based catalysts individually have advantages and
disadvantages properties [2] . Therefore effort to couple them in the
hope to bring forth a more efficient catalyst having parents’
advantages is of great importance. Herein, a series of cobalt-iron
nanocatalysts were prepared using some wet chemically methods
and were characterized using thermal analysis (TGA/DSC), N2 physisorption measurements such as BET, BJH, DH methods and
X-ray diffraction (XRD) techniques. The average sizes of
crystallites were determined below 100 nm from the half-width
of the most intense peak of the diffraction pattern using the
Scherrer equation. The crystallite sizes of catalysts were decreased
with increasing SiO content which clearly confirm. The
2
Brunauer-Emmett-Teller surface area (BET SA) measures of the
products show also that the increase of SiO ratio results in an
2
increase in the catalyst surface area linearly In the other hand, the
pore volume increases with increasing of SiO ratio to reach a
2
maximum at 50% SiO , and then decreases with further increasing
2
of SiO ratio. 2
references:
1. A. Y. Khodakov, W. Chu, P. Fongarland, Chem. Rev. 107
(2007) 1692.
2. R. M. Malek Abbaslou, A. Tavassoli, J. Soltan,
A. K. Dalai, Appl. Catal. A: Gen 367 (2009) 47.
Keywords: X-ray diffraction; Iron; Cobalt; Sol-Gel Process;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc