Molecular dynamics simulations of an Al2O3(0001 +/-, 0-10(II))/CeO2 (011 +/-,01-1(II)) interface system
2001 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 401, no 02-jan, 159-164 p.Article in journal (Refereed) Published
Constant stress, constant temperature (10 K, 300 K) molecular dynamics simulations were carried out with shell-model potentials for an infinite composite ceria-alumina slab with two free surfaces [alpha -Al2O3 (0001) and CeO2(011) and their opposite counterparts]. The interface introduces considerable structural and dynamical changes, both at the slab surfaces and in the center of the slab. Structurally, both oxide surfaces become effectively oxygen-terminated and the surface structures become disordered close to the interface. Dynamically, in the region near the 'alumina surface/ceria surface/alumina-ceria interface' 3-phase junction the ionic motion is considerably enhanced. Thus, in the interface region, the ionic mean-square displacements increase 2-3 times compared to the pure slabs. Moreover, the ions at the interface participate in a new kind of motion, not present in the pure oxide slabs: large occasional, but frequently reoccurring, back-and-forth ionic motions take place with square-amplitudes as large as similar to0.70 Angstrom (2).
Place, publisher, year, edition, pages
2001. Vol. 401, no 02-jan, 159-164 p.
three-way catalysts, molecular dynamic simulations, aluminium oxide, ceria, surface dynamics, interface structure, cerium dioxide, principles calculations, ceramic interfaces, alpha-alumina, 0001 surface, alpha-al2o3, adsorption, morphology, stability, crystal
IdentifiersURN: urn:nbn:se:kth:diva-21189ISI: 000172900200023OAI: oai:DiVA.org:kth-21189DiVA: diva2:339886
QC 201005252010-08-102010-08-10Bibliographically approved