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{Ti2(OPri)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-TiO2 embedded on a glassy matrix. After the heat treatment at temperatures above 900 °C, a pseudobrookite Fe2TiO5 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{Ti2(OPri)9}] should be a novel and efficient approach to the preparation of nanometric Fe/Ti oxides incorporated into a glassy matrix.

Graphical abstractThe picture represents a TEM image showing spherical iron–titanium oxide nanoparticles homogeneously incorporated in a glass mass.Figure optionsDownload full-size imageDownload as PowerPoint slide