Confinement ofInO3,InO6,andInBO3clusters in a glass matrix

Abstract

We report on the formation and detection of molecular aggregates of ${\mathrm{InO}}_{x}$ $(x=3,6)$ in a glass matrix. This result was achieved by simple melting of ${\mathrm{In}}_{2}{\mathrm{O}}_{3}$ in a ${\mathrm{B}}_{2}{\mathrm{O}}_{3}$ matrix, at dilution 0.05%. At higher concentrations, we have been able to confine clusters of the mixed compound ${\mathrm{InBO}}_{3},$ obtaining quantum dots of the indium borate embedded in the substrate. The average size of these agglomerates, evaluated in about 30 \AA{}, 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.