Electrosynthesis of nanocrystalline cerium oxide/layered silicate powders

Abstract

Cerium oxide/montmorillonite layered silicate powder nanocomposites were synthesized electrochemically. The produced nanocomposites were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy. X-Ray diffraction shows the nanocomposites retain the face-centered cubic structure of cerium oxide while incorporating delaminated platelets of the layered silicate into the matrix. By a negative shift in the OH stretching band position, infrared spectroscopy measurements indicate the layered silicates are delaminated. Photoluminescence background in the Raman spectra also shows the incorporation of the layered silicates within the cerium oxide matrix. The thermal properties of the nanocomposites were investigated with sintering and differential scanning calorimetry. The results indicate that low concentration of layered silicate mixed into the cerium oxide increases crystal growth rate whereas high concentration retards the increase of crystallite size during the densification process.