title: In situ growth, structure characterization, and enhanced photocatalysis of high-quality, single-crystalline ZnTe/ZnO branched nanoheterostructures.
abstract: Single-crystalline, high-quality branched ZnTe-core/ZnO-branch nanoheterostructures were synthesized by an in situ strategy in an environmental scanning electron microscope. Composition and structure characterization confirmed that ZnO nanowires were perfectly epitaxially grown on ZnTe nanowires as branches. Noticeably, growth temperature plays a crucial role in determining the density and diameter of the ZnO nanobranches on ZnTe nanowires: a higher growth temperature leads to ZnO nanowires with higher density and smaller diameter. It was demonstrated that ZnO nanobranches exhibited a selective nucleation behavior on distinct side facets of ZnTe nanowires. Highly ordered ZnO nanobranches were found epitaxially grown on {211} facet of ZnTe nanowires, while there was no ZnO nanowire growth on {110} facet of ZnTe nanowires. Using first-principles calculation, we found that surface energy of distinct side facets has a strong impact on ZnO nucleation, and confirm that {211} facet of ZnTe nanowires is energetically more favorable for ZnO nanowire growth than {110} facet, which is in good agreement with our experimental findings. Remarkably, such unique ZnTe/ZnO 3D branched nanowire heterostructures exhibited improved photocatalytic abilities, superior to ZnO nanowires and ZnTe nanowires, due to the much enhanced effective surface area of their unique architecture and effective electron-hole separation at the ZnTe/ZnO interfaces.
authors.affiliation: State Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, P. R. China.
authors.forename: Yanghui
authors.initials: Y
authors.lastname: Sun
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhao
authors.forename: Jingyun
authors.initials: J
authors.lastname: Gao
authors.forename: Yu
authors.initials: Y
authors.lastname: Ye
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Rui
authors.initials: R
authors.lastname: Zhu
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.forename: Lun
authors.initials: L
authors.lastname: Dai
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Liao
authors.forename: Dapeng
authors.initials: D
authors.lastname: Yu
mesh_terms: D002384:Catalysis; D003460:Crystallization; D008027:Light; D049329:Nanostructures / Q000737:chemistry; D053770:Nanowires / Q000737:chemistry; D013696:Temperature; D014466:Ultraviolet Rays; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D015034:Zinc Oxide