Structural analysis and shape-dependent catalytic activity of Au, Pt and Au/Pt nanoparticles

Metallic nanoparticles of Au, Pt and Pt/Au have been synthesized using a chemical reduction approach. The structural characterization of these metallic nanoparticles has been carried out using conventional transmission electron microscopy (TEM) and high resolution transmission electron microscopy (H...

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Detalles Bibliográficos
Autores: Esparza,R., Rosas,G., Valenzuela,E., Gamboa,S.A., Pal,U., Pérez,R.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:Brasil
Institución:Matéria (Rio de Janeiro. Online)
Repositorio:Matéria (Rio de Janeiro. Online)
Idioma:inglés
OAI Identifier:oai:scielo:S1517-70762008000400002
Acceso en línea:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1517-70762008000400002
Access Level:acceso abierto
Palabra clave:gold
platinum
nanoparticles
chemical reduction synthesis
electron microscopy
structural determination
electrochemical characterization
Descripción
Sumario:Metallic nanoparticles of Au, Pt and Pt/Au have been synthesized using a chemical reduction approach. The structural characterization of these metallic nanoparticles has been carried out using conventional transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HR-TEM) techniques. HR-TEM images of Pt nanoparticles reveal their fcc-like structures, in the [103] and [011] orientations. However, in case of Au, the main structures are fcc-like and decahedral morphologies with five-fold symmetry axes. The structure of the gold nanoparticles was verified through their theoretically-simulated images, using a multislice approach of the dynamical theory of electron diffraction. These small particles have been used as electrocatalysts in Nafion membranes for fuel cell applications. The electrochemical characterization of the membranes shows that the Pt dispersion gives best performance for fuel cell applications.