Green and Short Preparation of CeO₂ Nanoparticles with Large Specific Surface Area by Spray Pyrolysis

Green and short preparation of CeO₂ nanoparticles with large specific surface area from rare earth extraction (CeCl₃) was successfully achieved by spray pyrolysis (SP). In this method, a precursor solution is first prepared by mixing CeCl₃, C₆H₈O, and H₂O in the requisite quantities. Subsequently, the precursor consisting of a mixture of CeO₂ and C was obtained by SP method by using the precursor solution. Finally, the calcination at 500 °C~800 °C in air for two hours to transform the precursor to CeO₂ nanoparticles. Thermodynamic analysis and experimental studies were performed to determine the optimal SP temperature and citric acid amount. The results indicated that the maximum specific surface area (59.72 m²/g) of CeO₂ nanoparticles were obtained when the SP temperature was 650 °C and the molar ratio of citric acid to CeCl₃ was 1.5.