Confinement of InO3, InO6, and InBO3 clusters in a glass matrix

We report on the formation and detection of molecular aggregates of InOx (x53,6) in a glass matrix. This result was achieved by simple melting of In2O3 in a B2O3 matrix, at dilution 0.05%. At higher concentrations, we have been able to confine clusters of the mixed compound InBO3, obtaining quantum dots of the indium borate embedded in the substrate. The average size of these agglomerates, evaluated in about 30 Å , does not change, increasing the dilution in the range 0.3-2.0 %. These results are of particular importance for the confinement of quantum dots in a glass matrix. The characterization of the samples was performed by extended x-ray-absorpion fine-structure and x-ray-diffraction spectroscopies.