ACr2O4 /SiO2 (A = Zn, Cu, Cd) nanocomposites, their preparation and physical properties

This article presents preparation and characterization of zinc, copper and cadmium chromites nanocrystals embedded in a silica matrix. The ZnCr2O4/SiO2, CuCr2O4/SiO2 and CdCr2O4/SiO2 samples were prepared by a conventional sol-gel method using HNO3 as an acid catalyst, formamide as a modifier, methanol as a solvent and TEOS. Final heat treatment of the nanocomposites was carried out at temperatures in the range of 900 – 1100°C. The resulting samples were characterized by X-ray diffraction, High Resolution Transmission Electron Microscopy, and magnetic measurements.