Self-assembly of cerium compound nanopetals via a hydrothermal process: Synthesis, formation mechanism and properties

Nanopetals of cerium hydroxycarbonate have been synthesized via a controlled hydrothermal process in a mixed water–ethanol medium. Electron microscopy indicates that each microsized flower consists of tens to hundreds of cerium hydroxycarbonate nanopetals. These nanopetals have a very large aspect ratio: a width as large as 10 μm, with a thickness as thin as 10 nm. The formation of the cerium compound depends strongly on the composition of the precursors, and is attributed to the favored ethanol oxidation by Ce(IV) ions over Ce(IV) hydrolysis process. Raman studies showed that microflower CeO2 preferentially stabilizes O2 as a peroxide species on its surface for CO oxidation.