Nanotubos de Carbono Ancorados em Filmes de Nanopartículas de Ouro para Utilização em Sensores Ópticos

Abstract

Nanomaterials are materials in nanoscale, that have a use for at least one of their unique properties arising from this size scale. These unique properties arise when the material reaches a size smaller than the called "critical size", size that separates the properties of materials "bulk" and nanoparticles. Among the nanomaterials, carbon nanotubes (CNTs) have great prominence due to their unique and fantastic properties, including mechanical, optical and conductive properties. Carbon nanotubes are formed by graphene sheets rolled into a cylindrical shape and its properties depend on the number of layers and how they were rolled up. Metallic nanoparticles of Au, Ag and Cu are also nanomaterials with attractive optical properties, due to the presence of the plasmon absorption (absorption resulting from the collective oscillation of electrons) in the visible spectral region. Studies show that CNTs also possess plasmonic absorption, being extremely attractive their use in optical sensors. Proposed for this work, the anchoring of CNTs multi-walled (MWCNT) functionalized with thiol groups (-SH), from cysteamines, in films of gold nanoparticles deposited on silica for future use in optical sensors. The produced samples were characterized by the methods of X- ray diffraction with accessory for thin films, Raman spectroscopy, UV-Vis spectroscopy and transmission electron microscopy.