title: Rewritable superhydrophilic-superhydrophobic patterns on a sintered titanium dioxide substrate.
abstract: This Letter describes a new fabrication process for superhydrophilic-superhydrophobic patterns on a TiO(2) surface using a combination of an inkjet technique and the site-selective decomposition of a self-assembled monolayer (SAM) by a photocatalytic reaction under UV irradiation. To induce high surface wettability, we carried out simple calcination of a Ti substrate. The substrate was thus oxidized to titanium oxide and had a vortex-like rough morphology, which was suitable for the formation of wettability patterns. Furthermore, the substrate can be regenerated after elimination of the superhydrophilic-superhydrophobic patterns by the photocatalytic decomposition of TiO(2) using UV irradiation, and the patterns are deposited again. The renewed surface that we created had a wettability pattern that was different from the preceding pattern. This process is based on a TiO(2) surface and should offer a renewable, resource-saving, and environmentally friendly methodology for the formation of wettability patterns.
authors.affiliation: Photocatalyst group, Kanagawa Academy of Science and Technology, KSP West 614, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Nakata
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Nishimoto
authors.forename: Yumi
authors.initials: Y
authors.lastname: Yuda
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ochiai
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Murakami
authors.forename: Akira
authors.initials: A
authors.lastname: Fujishima
mesh_terms: D057927:Hydrophobic and Hydrophilic Interactions; D007281:Ink; D011327:Printing; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; C009495:titanium dioxide; D014025:Titanium