Síntese e caracterização de nanocompósitos Ni: SiO2 processados na forma de filmes finos Synthesis and characterization of Ni: SiO2 nanocomposites processed as thin films

• Main Authors: Paulo Sérgio Gouveia, Marcia Tsuijama Escote, Elson Longo, Edson R. Leite, Neftali L. V. Carreño, Fabio C. Fonseca, Renato de F. Jardim
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Química 2005-10-01
• Series: Química Nova
• Subjects: polymeric precursor method; thin films; magnetic nanoparticles
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422005000500022

<abstract language="eng">We have produced nanocomposite films of Ni:SiO2 by an alternative polymeric precursor route. Films, with thickness of ~ 1000 nm, were characterized by several techniques including X-ray diffraction, scanning electron microscopy, atomic force microscopy, flame absorption atomic spectrometry, and dc magnetization. Results from the microstructural characterizations indicated that metallic Ni-nanoparticles with average diameter of ~ 3 nm are homogeneously distributed in an amorphous SiO2 matrix. Magnetization measurements revealed a blocking temperature T B ~ 7 K for the most diluted sample and the absence of an exchange bias suggesting that Ni nanoparticles are free from an oxide layer.