title: Adhesion and Atomic Structures of Gold on Ceria Nanostructures: The Role of Surface Structure and Oxidation State of Ceria Supports.
abstract: We report an aberration-corrected electron microscopy analysis of the adhesion and atomic structures of gold nanoparticle catalysts supported on ceria nanocubes and nanorods. Under oxidative conditions, the as-prepared gold nanoparticles on the ceria nanocubes have extended atom layers at the metal-support interface. In contrast, regular gold nanoparticles and rafts are present on the ceria nanorod supports. Under the reducing conditions of water-gas shift reaction, the extended gold atom layers and rafts vanish. In addition, the gold particles on the nanocubes change in morphology and increase in size while those on the nanorods are almost unchanged. The size, morphology, and atomic interface structures of gold strongly depend on the surface structures of ceria supports ((100) surface versus (111) surface) and the reaction environment (reductive versus oxidative). These findings provide insights into the deactivation mechanisms and the shape-dependent catalysis of oxide supported metal catalysts.
authors.affiliation: †Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
authors.forename: Yuyuan
authors.initials: Y
authors.lastname: Lin
authors.affiliation: ‡Chemical Science Division and Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
authors.forename: Zili
authors.initials: Z
authors.lastname: Wu
authors.affiliation: §Electron Microscopy Center, Argonne National Laboratory, Argonne, Illinois 60439, United States.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Wen
authors.affiliation: ⊥Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
authors.forename: Kunlun
authors.initials: K
authors.lastname: Ding
authors.affiliation: ∥2112 Vincenzo Walkway, San Jose, California 95133, United States.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Yang
authors.affiliation: ⊥Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Poeppelmeier
authors.affiliation: †Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Marks
mesh_terms: D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D043942:Nanotubes / Q000737:chemistry / Q000648:ultrastructure; D010084:Oxidation-Reduction
chemical_list: D002563:Cerium; C030583:ceric oxide; D006046:Gold
keywords: Gold; aberration corrected STEM HAADF; adhesion; atomic structures; catalysis; ceria; nanocube; nanorods