Mechanical stirring and synergistic effect of Pr3+/Pr4+ and Ce4+ in improving the low-temperature reducibility of Pr-doped ceria nanoparticles

Abstract

We report that shape/size-controlled high surface area CeO2 and Pr-doped CeO2 solid solution nanoparticles were synthesized using a facile hydrothermal method. The effect of mechanical stirring during the initial stage of synthesis on the shape/size control, phase homogeneity of mixed oxides, and reducibility of materials were investigated. The results indicate that a synergistic effect between Ce4+ and Pr3+/Pr4+ in the Pr-doped CeO2 nanoparticles facilitates oxygen mobility within the solid solution lattice structure hence improving the reducibility of doped ceria materials at lower temperature as compared to the pure CeO2. Characterization techniques that were employed in this study include Powder X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), BET surface area and Hydrogen Temperature Programmed Reduction (H2-TPR).