An improved method for preparation of Ce0.8Pr0.2OY solid solutions with nanoparticles smaller than 10 nm

Abstract

Ce0.8Pr0.2OY solid solutions with ultrafine crystalline sizes and high specific surface area were prepared by an improved citrate precursor method, where a nitrogen treatment was added prior to calcinations in air. The samples were characterized by TG-DSC, Raman spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and BET nitrogen adsorption. XRD and Raman results show that the formation of Ce0.8Pr0.2OY solid solutions typical of the fluorite-like cubic structure with oxygen vacancies occurs when the Ce–Pr citrate precursors are heated at high temperature in the nitrogen atmosphere. Subsequent calcinations at a low temperature in air to remove carbon species have no apparent effects on the formed solid solutions. Ce0.8Pr0.2OY solid solution prepared by the improved citrate precursor method at 800°C has ultrafine nanoparticles of less than 10 nm and high specific surface area of 92.1 m2/g, while the sample prepared by the conventional citrate precursor method has mean particle size of 62.1 nm and specific surface area of 18.1 m2/g. Furthermore, Ce–Pr solid solution by the improved method have the mesoporous structure, more lattice defects and oxygen vacancies, which will have a promising application in the catalyst region as well as SOFC field.