Nanocomposites materials generated from a spray

• Autor(a) principal: Marques,R.F.C.
• Data de Publicação: 2009
• Outros Autores: Caiut,J.M.A., Paiva-Santos,C.O., Ribeiro,S.J.L., Messaddeq,Y., Garcia,C., Neumeyer,D., Dexpert,H., Verelst,M., Dexpert-Ghys,J.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Physics
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332009000200009
• topic: Spray-pyrolysis; Nano-powders; Ferrihydrite; Hematite; Boehmite; Alumina

The Spray Pyrolysis (SP) process has been employed at moderate temperature (470-970 K) for the synthesis of micro- and nano-particles of hydrated metal oxides and of related nanocomposites. It has been applied to iron nitrate solutions, without or with the addition of sodium chloride as a flux. After removal of the flux, nanocomposites of ferrihydrite (5Fe2O3,9H2O) / hematite (α- Fe2O3) / and an amorphous Fe2O3 are obtained, with surface area 140 m²/g. It has been applied also to a sol of Aluminum-tri-sec-butoxide, without or with activation by europium or terbium ions. Boehmite (γ-AlOOH) powders are synthesized at 470 K, with surface area equal to 180 m²/g. Transition alumina (γ-Al2O3) are synthesized at 970 K. Nanocomposites made by reaction of the boehmite or γ-Al2O3 particles with the amino acid asparagin (ASN) have been prepared and characterized. The luminescence of the Eu3+ or Tb3+ doped nanocomposites has been investigated: they can be considered as bio-compatible luminescent nanoparticles.