title: Controlled Growth of Ceria Nanoarrays on Anatase Titania Powder: A Bottom-up Physical Picture.
abstract: The leading edge of catalysis research motivates physical understanding of the growth of nanoscale oxide structures on different supporting oxide materials that are themselves also nanostructured. This research opens up for consideration a diverse range of facets on the support material, versus the single facet typically involved in wide-area growth of thin films. Here, we study the growth of ceria nanoarchitectures on practical anatase titania powders as a showcase inspired by recent experiments. Density functional theory (DFT)-based methods are employed to characterize and rationalize the broad array of low energy nanostructures that emerge. Using a bottom-up approach, we are able to identify and characterize the underlying mechanisms for the facet-dependent growth of various ceria motifs on anatase titania based on formation energy. These motifs include 0D clusters, 1D chains, 2D plates, and 3D nanoparticles. The ceria growth mode and morphology are determined by the interplay of several factors including the role of the common cation valence, the interface template effect for different facets of the anatase support, enhanced ionic binding for more compact ceria motifs, and the local structural flexibility of oxygen ions in bridging the interface between anatase and ceria structures.
authors.affiliation: Department of Materials Science and Engineering, Chungnam National University , 99-Daehakro, Daejeon 34134, Republic of Korea.
authors.forename: Hyun You
authors.identifier: 0000-0001-8105-1640
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Hybertsen
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States.
authors.forename: Ping
authors.identifier: 0000-0001-8363-070X
authors.initials: P
authors.lastname: Liu
mesh_terms: D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D011208:Powders; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013816:Thermodynamics; D014025:Titanium / Q000737:chemistry*
chemical_list: D011208:Powders; C009495:titanium dioxide; D002563:Cerium; C030583:ceric oxide; D014025:Titanium; D010100:Oxygen
keywords: Oxide interfaces; ceria; density functional theory calculations; epitaxial growth; formation energy; nanostructure growth; titania