Crystalline Ce(III)-La(III) double basic carbonates: a chemical shortcut to obtain nanometric La(III)-doped ceria.

MATÍAS JOBBÁGY; CECILIA SORBELLO; ELSA E. SILEO

JOURNAL OF PHYSICAL CHEMISTRY

American Chemical Society

Lugar: Washington; Año: 2009 vol. 113 p. 10853 - 10857

0022-3654

The controlled decomposition of crystalline Ce1-xLax(OH)CO3 samples to give nanocrystalline Ce1-xLaxO2-d solid solutions are studied as a function of temperature and La(III) content. The hexagonal basic carbonates, related to the mineral bastnaesite, show to be suitable precursors for the obtainment of Ce(IV-III),La(III) oxides when exposed to O2 at mild temperatures (250 °C). The oxidation of Ce(III) centers triggers the massive decomposition of the whole precursor, acting as a chemical shortcut to achieve the domain of ceria phases, at temperatures 200 °C lower than the traditional procedures. The mixed oxides exhibit higher surface areas than those obtained for traditional coprecipitation-thermal decomposition procedures, achieving values in the range of those oxides prepared by costly surfactant assisted methods.