title: Site-specific growth of Au particles on ZnO nanopyramids under ultraviolet illumination.
abstract: In this work, wurtzite ZnO nanocrystals with unique "pyramid" morphology were firstly prepared via solvothermal synthesis. It was determined that the ZnO nanopyramids are grown along the polar c-axis with the vertexes pointing to the [001] direction. When the mixture of ZnO nanopyramids and Au precursor (HAuCl(4)) was exposed to ultraviolet (UV) illumination, Au particles were site-specifically formed on the vertexes of ZnO nanopyramids. The obtained Au/ZnO nanocomposite showed significantly enhanced photocatalytic activity as compared to the bare ZnO nanopyramids. First-principles based calculations well explained the formation of ZnO nanopyramids as well as the site-specific growth of Au, and revealed that during the photocatalysis process the Au particles can accommodate photoelectrons and thus facilitate the charge separation.
authors.affiliation: Advanced Membrane and Porous Materials Center and Imaging and Characterization Core Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
authors.forename: Ke Xin
authors.initials: KX
authors.lastname: Yao
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Lan
authors.initials: L
authors.lastname: Zhao
authors.forename: Hua Chun
authors.initials: HC
authors.lastname: Zeng
authors.forename: Yu
authors.initials: Y
authors.lastname: Han
mesh_terms: D001391:Azo Compounds / Q000737:chemistry; D002384:Catalysis; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D053761:Nanocomposites / Q000737:chemistry; D014466:Ultraviolet Rays; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D001391:Azo Compounds; C100258:methyl orange; D006046:Gold; D015034:Zinc Oxide