4.8 Article

Synthesis of Ceria-Zirconia Nanocrystals with Improved Microstructural Homogeneity and Oxygen Storage Capacity by Hydrolytic Sol-Gel Process in Coordinating Environment

Journal

ADVANCED FUNCTIONAL MATERIALS
Volume 22, Issue 13, Pages 2867-2875

Publisher

WILEY-V C H VERLAG GMBH
DOI: 10.1002/adfm.201200380

Keywords

colloidal nanocrystals; nanoscale polymorphs; hydrolytic synthesis; sol-gel processes

Funding

  1. CSIC/CNR project [2010IT0001]
  2. SOLAR project [DM19447]
  3. European Regional Development Funds European (ERDF, FEDER Programa Competitivitat de Catalunya)
  4. Spanish Government projects Consolider Ingenio [CSD2009 00013 IMAGINE, CSD2009 00050 MULTICAT]
  5. MICINN project NANO-EN-ESTO [MAT2010-21510]
  6. Spanish MICINN [MAT2010-15138]
  7. ICREA Funding Source: Custom

Ask authors/readers for more resources

Ceriazirconia solid solution nanocrystals, (1-x)CeO2xZrO2, 0 = x = 1, are prepared by solgel processing in dodecylamine of solutions obtained by forced hydrolysis of inorganic salts. The as-prepared nanoparticles have a ceria cubic structure, up to x = 0.35, or are amorphous. Heat-treatment is carried out at temperatures ranging from 500 to 800 degrees C, the latter temperature begin suitable to obtain solid solutions throughout the composition range. For all the heating temperatures and x values, the fluorite cubic structure of pure CeO2 transforms to a mixture (c') of the cubic c and tetragonal t? phases for x = 0.35, and to tetragonal t phase only for x = 0.8 at 650 degrees C, x = 0.65 at 800 degrees C, and, to a very limited extent, x = 0.5 at 1000 degrees C. No evidence is obtained at low x values of the t phase, which is detrimental to the oxygen storage capacity. Prolonged heating at 1000 degrees C demonstrates that only for x = 0.65 a limited separation of CeO2-rich nanocrystals occurs. The samples undergo the same transition without simultaneous occurrence of different phases, apart for the two mentioned limited cases. This result is attributed to the intimate mixing of the metal cations even in the early stages of processing. In as-prepared samples the Zr distribution becomes inhomogeneous when going from x = 0.2 to x = 0.35, but no early phase separations appear. The oxygen storage capacity is favorably influenced by the persistence of the cubic c' phase.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.8
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available