INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
MODELING FREE AND SURFACTANT-PROTECTED METAL NANOPARTICLES
Autor/es:
JIMENA OLMOS ASAR, MARTIN LUDUEÑA, ANA SPITALE, MARCELO MARICAL
Lugar:
CANCUN
Reunión:
Simposio; NANOSTRUCTURED MATERIALS AND NANOTECHNOLOGY; 2011
Institución organizadora:
MRS ; SOCIEDAD MEXICANA DE MATERIALES A.C.
Resumen:
Metallic
nanoparticles are perhaps one of the most outstanding applications of
nanotechnology due to potential use of these nanostructures on diverse
fields, i.e. biosensors, catalysis, drug delivery and construction
of nano-circuitsi,ii,iii..
Preparation,
conservation and protection of metallic nanoparticles require
passivation with organic ligand molecules if they will remains in a
colloidal suspension. When nanoparticles are made of gold, a relatively
easy way of protect them is through organic molecular self-assembly,
particularly with thiols molecules due to the strong interaction
between sulfur and gold atoms. Self-assembly monolayers (SAMs) have
been intensively studied, at experimentaliv,v,vi and theoretical levelvii,viii,ix,x,
on extended gold (111) surfaces. Nevertheless, a clear understanding
about some fundamental structural aspects of passivated Au
nanoparticles in the range of 1-10 nm still does not exist.
In
the present talk we show the application of a new semiempirical
potential recently developed in our Lab to describe molecule-metal
interfaces in a realistic way. Using Density Functional calculations
(DFT) in combination with the bond-order concept we have developed a
new semiempirical framework which is very simple and easy to implement
in standard molecular dynamics codes. In particular we show the effect
of soft and hard surfactant on the structure of gold nanoparticles.
Finally,
we will show very recent studies which involve the nucleation and
growth processes of bimetallicl NP´s carried out in solution under
control of the chemical potential of the metal ions.
i A. Manna, T. Imae, K. Aoi, M. Okazaki, Mol. Simul. 29 (2003) 661
ii R. Hong, G. Han, J. M. Fernández, B. J. Kim, N. S. Forbes, V. M. Rotello, J. Am. Chem. Soc. 128 (2006) 1078
iii M. M. Mariscal and S. A. Dassie, Recent Advances in Nanoscience, Research Signpost Pub. - Trivandrum, India (2007).
iv A. Ulman, S. D. Evans, Y. Shnidman, R. Sharma, E. Eilers, J. C. Chang, J. Am. Chem. Soc. 113 (1991) 1499
v D. J. Lavrich, S. M. Wetterer, S. L. Bernasek, G. Scoles, J. Phys. Chem. B 102 (1998) 3456
vi C Vericat, G A Benitez, D E Grumelli, M E Vela and R C Salvarezza, J. Phys.: Condens. Matter 20 (2008) 184004
vii J. Hautman, M. Klein, J. Chem. Phys. 91 (1989) 4994
viii A. Pertsin, M. Grunze. Langmuir 10 (1994) 3668
ix Y. Yourdshahyan, A. M. Rappe, J. Chem. Phys. 117 (2002) 825
x M. J. Esplandiú, M. L. Carot, F. P. Cometto, V. A. Macagno, E. M. Patrito, Sur. Sci. 600 (2006) 155