Sol-gel processing of a bimetallic alkoxide precursor confined in a porous glass matrix: a route to novel glass/metal oxide nanocomposites.
In this work we present the utilization of the heterometallic alkoxide [FeCl{Ti(2)(OPr(i))(9)}] as the first sol-gel single-source precursor to achieve nanocomposites made of iron and titanium oxides incorporated into Porous Vycor Glass (PVG). The nanocomposites were prepared by the impregnation of the precursor in a PVG plate followed by hydrolysis reactions. Different samples were obtained by further thermal treatment of the hydrolyzed sample. The nanocomposites were characterized by UV-vis-NIR, Raman and EPR spectroscopies, XRD and TEM. The results indicate that the room-temperature hydrolyzed samples are formed by nanoparticles of FeOOH and brookite-TiO(2) embedded on a glassy matrix. After the heat treatment at temperatures above 900 degrees C, a pseudobrookite Fe(2)TiO(5) was formed. All samples present high transparency and homogeneity. The results showed here indicate that the sol-gel process using the single-source precursor [FeCl{Ti(2)(OPr(i))(9)}] should be a novel and efficient approach to the preparation of nanometric Fe/Ti oxides incorporated into a glassy matrix.
Departamento de Química, Universidade Federal do Paraná, CP 19081, CEP 81531-990, Curitiba, PR, Brazil.
Willian G
WG
Menezes
Pedro H C
PH
Camargo
Marcela M
MM
Oliveira
David J
DJ
Evans
Jaísa F
JF
Soares
Aldo J G
AJ
Zarbin