title: ZnO dense nanowire array on a film structure in a single crystal domain texture for optical and photoelectrochemical applications.
abstract: A single crystal domain texture quality (a unique in-plane and out-of-plane crystalline orientation over a large area) ZnO nanostructure of a dense nanowire array on a thick film has been homogeneously synthesized on a-plane sapphire substrates over large areas through a one-step chemical vapor deposition (CVD) process. The growth mechanism is clarified: a single crystal [02(-)1] oriented ZnAl(2)O(4) buffer layer was formed at the ZnO film and the a-plane sapphire substrate interface via a diffusion reaction process during the CVD process, providing improved epitaxial conditions that enable the synthesis of the high crystalline quality ZnO nanowire array on a film structure. The high optoelectronic quality of the ZnO nanowire array on a film sample is evidenced by the free exitonic emissions in the low-temperature photoluminescence spectroscopy. A carrier density of ~10(17) cm(-3) with an n-type conductivity of the ZnO nanowire array on a film sample is obtained by electrochemical impedance analysis. Finally, the ZnO nanowire array on a film sample is demonstrated to be an ideal template for a further synthesis of a single crystal quality ZnO-ZnGa(2)O(4) core-shell nanowire array on a film structure. The fabricated ZnO-ZnGa(2)O(4) sample revealed an enhanced anticorrosive ability and photoelectrochemical performance when used as a photoanode in a photoelectrochemical water splitting application.
authors.affiliation: School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan. zhong.miao@scale.t.u-tokyo.ac.jp
authors.forename: Miao
authors.initials: M
authors.lastname: Zhong
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sato
authors.forename: Mario
authors.initials: M
authors.lastname: Kurniawan
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Apostoluk
authors.forename: Bruno
authors.initials: B
authors.lastname: Masenelli
authors.forename: Etsuo
authors.initials: E
authors.lastname: Maeda
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ikuhara
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Delaunay
mesh_terms: D003460:Crystallization / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D008027:Light; D008422:Materials Testing; D008567:Membranes, Artificial; D043942:Nanotubes / Q000737:chemistry* / Q000528:radiation effects; D010777:Photochemistry / Q000295:instrumentation*; D015034:Zinc Oxide / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D008567:Membranes, Artificial; D015034:Zinc Oxide