INQUIMAE   12526
INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
FILMS OF NANOPARTICLES EMBEDDED IN MESOPOROUS SIO2 ARRAYS
Autor/es:
M. CLAUDIA MARCHI; ANA CECILIA SPEDALIERI; SARA ALDABE BILMES
Lugar:
Porto de Galinhas- Pernambuco- Brazil
Reunión:
Congreso; XVth International Sol-Gel Conference; 2009
Institución organizadora:
International Sol-gel Society
Resumen:
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Building
a device based on the unique properties of nanoparticles (NPs), such as their
size dependent optical response usually requires a substrate. On the other
hand, most of semiconductor Q-dots proven to have absorption and luminescence
tuned by their size are extremely toxic. A proposed solution to these problems
is the encapsulation of NPs in an inert matrix. However, the resulting
composite material, Q-dot@SiO2, must be stable and robust,
maintaining the desired properties for long terms, and when needed the surface
of Q-dots must be exposed to the surrounding medium. In addition, the synthesis
pathway requires good reproducibility.
Here,
we present the optical response of CdX (X = S, Se) and Bi2S3
embedded in SiO2 mesoporous (MP) films with regular structure, which
is defined by the amphiphilic employed
for their synthesis. The encapsulated Q-dots are synthesized inside pores by
reaction between the metallic precursor and the chalcogenide.
The optical response of embedded Q-dots is
controlled by the size of pores and is comparable to that of Q-dot colloids;
even the emission band is wider when NPs are encapsulated. The preparation
method for each Q-dot@SiO2 is highly reproducible, and we found a stable
optical response for several months, longer than that found for their
respective colloids.