Preparation of CeO<inf>2</inf> nano rods through a sonication-assisted precipitation

Abstract

A CeO2 nanopowder has been synthesized using sonication-assisted precipitation. The use of ultrasonics during precipitation showed potential morphology control during synthesis. The sonication-assisted precipitation with highly aqueous base (20 M NaOH) successfully induced the formation of a one-dimensional nanostructure of CeO2 rods with a homogeneous shape and size (TEM: 24 nm diameter and 129 nm long). A conventional precipitation under the same conditions provided the CeO2 in nonuniform sizes and shapes. Heat treatment (1100C for 4 h) was required for CeO2 formation when (NH4)2C2O4 was used instead of NaOH. The concentration of the precipitation agent (15-20 M) strongly affected the size and shape of the product. Importantly, according to the temperature-programmed reduction/oxidation study, the CeO2 prepared using the sonication-assisted route showed a relatively higher level of reversible oxygen storage capacity (2384 μmol/g), compared with the CeO 2 prepared by conventional route (1748 μmol/g). © 2014 The American Ceramic Society.