title: Simultaneous Formation and Spatial Patterning of ZnO on ITO Surfaces by Local Laser-Induced Generation of Microbubbles in Aqueous Solutions of [Zn(NH3)4]2.
abstract: We demonstrate the simultaneous formation and spatial patterning of ZnO nanocrystals on an indium-tin oxide (ITO) surface upon local heating using a laser (1064 nm) and subsequent formation of microbubbles. Laser irradiation of an ITO surface in aqueous [Zn(NH3)4]2+solution (1.0 × 10-2M at pH 12.0) under an optical microscope produced ZnO nanocrystals, the presence of which was confirmed by X-ray diffraction analysis and Raman microspectroscopy. Scanning the focused laser beam over the ITO surface generated a spatial ZnO pattern (height: ∼60 nm, width: ∼1 μm) in the absence of a template or mask. The Marangoni convection generated in the vicinity of the microbubbles resulted in a rapid concentration/accumulation of [Zn(NH3)4]2+around the microbubbles, which led to the formation of ZnO at the solid-bubble-solution three-phase contact line around the bubbles and thus afforded ZnO nanocrystals on the ITO surface upon local heating with a laser.
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.|Department of Chemistry, Faculty of Science, Hokkaido University , Kita-10, Nishi-8, Kita-ku, Sapporo 060-0810, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Fujii
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Fukano
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Hayami
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ozawa
authors.affiliation: Department of Physics, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Eiro
authors.initials: E
authors.lastname: Muneyuki
authors.affiliation: Department of Chemistry, Faculty of Science, Hokkaido University , Kita-10, Nishi-8, Kita-ku, Sapporo 060-0810, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Kitamura
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Masa-Aki
authors.identifier: http://orcid.org/0000-0002-1230-3848
authors.initials: MA
authors.lastname: Haga
keywords: ZnO thin film; hydrothermal reaction; laser local heating; microbubble; micropatterning