Structure and Optical Properties of CeO2 Nanoparticles Synthesized by Precipitation

Cerium dioxide (CeO₂) has special electrical and optical properties, and chemical and thermal stability. It has been used in semiconductor devices and as a luminescent material. In this work, CeO₂ nanoparticles were synthesized by the precipitation method and the product annealed at various temperatures. Thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC) results show that the optimum annealing temperature for fabrication of CeO₂ nanoparticles is greater than 500°C. When the calcination temperature is increased from 550°C to 1050°C, Fourier-transform infrared (FTIR) results show that the water and impurities are almost completely removed, after calcination at 750°C. The x-ray diffraction (XRD) results suggest that the synthesized CeO₂ exhibits a cubic fluorite structure. The crystallite size of the CeO₂ increases from 8 nm to 75 nm when the calcination temperature is increased from 550°C to 1050°C. The absorption spectrum in the ultraviolet (UV) region from 372 nm to 395 nm demonstrates their applicability as UV-filter materials, and the shift of the estimated E _g,eff from 3.21 eV to 3.65 eV demonstrates their applicability in photoelectric devices. CeO₂ would be potentially important for applications such as insulator structures, stable capacitor devices, and light-emitting diodes (LEDs).