Search

Using solgel method Nd2O3−SiO2 binary oxide systems were prepared. The binary oxide transformed from the amorphous phase to nanocrystalline phase upon heat treatment in air. Characterization of the Nd2O3–SiO2 was carried out by using X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The effect of the sintering temperature and time on the evolution of the binary oxide system was discussed. It is found that sintering time plays a pivotal role to obtain Nd2O3– SiO2 nanocomposite. At temperature of 900 ◦C, the sample was sintered for 12 h and monoclinic Nd2O3 nanocrystallites, with average crystallite size ≈ 12 nm, were obtained.

Microstructure and surface morphology of AgO nanocrystallites (25 nm) supported on SiO2 and subjected to heat treatment in air up to 500 ◦C have been studied by transmission electron microscopy, scanning electron microscopy, and the Fourier transform infrared spectroscopy measurements. It has been found that heating at 500 ◦C resulted in spreading of AgO over silica and formation of quasi two-dimensional amorphous phase (silicate precursor) exhibiting very weak band at 566 cm−1 have appeared in the Fourier transform infrared spectroscopy. Nanocrystalline silver silicate of unde ned structure formed at 300 500 ◦C.