title: Novel functionalization of Ti-V alloy and Ti-II using atomic layer deposition for improved surface wettability.
abstract: Surface wettability characteristics of commercially pure titanium (CP-Ti/Ti-II) and titanium Grade 5 alloy (Ti-6Al-4V/Ti-V) with 10nm-thick atomic layer deposited (ALD) TiO2 from Tetrakis DiEthyl Amino Titanium and water vapor were studied in conjunction with cleaning steps before and after the ALD treatment. The wettability characteristics of rough Ti-II and Ti-V samples were investigated after each step, that is, as received, after de-ionized (DI) water rinse followed by N2 drying, sonication in methanol, ALD treatment, and post-ALD DI water rinse. Samples without ALD or cleaning treatments were hydrophobic to variable extents, depending on exposure to different environments, surface impurities, roughness, and aging. Surface treatments reported in the literature resulted in hydrophilic/hydrophobic surfaces likely due to organic and/or inorganic impurities. In this study, (i) it is established that it is critically important to probe surface wettability after each substrate treatment; (ii) both Ti-II and Ti-V surfaces are found to become more hydrophilic after each one of the sequential treatments used; and (iii) independently of the initial wettability characteristics of Ti-II and Ti-V surfaces, the aforementioned treatments result in a water contact angle well below 10°, which is an important factor in cellular response. X-ray photoelectron spectroscopy of ALD titania films indicated trace impurities in them. Grazing incidence X-ray diffraction suggested amorphous ALD TiO2 at 200 °C; anatase TiO2 was obtained with as little as 5 min annealing at 600 °C in nitrogen.
authors.affiliation: Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA.
authors.forename: Sweetu
authors.initials: S
authors.lastname: Patel
authors.affiliation: Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA.
authors.forename: Arman
authors.initials: A
authors.lastname: Butt
authors.affiliation: Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL 60607, USA; Micron Technology, Inc., Boise, ID 83716, USA.
authors.forename: Qian
authors.initials: Q
authors.lastname: Tao
authors.affiliation: Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL 60607, USA.
authors.forename: Jorge Iván
authors.initials: JI
authors.lastname: Rossero A
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago, Chicago, IL 60612, USA.
authors.forename: Dmitry
authors.initials: D
authors.lastname: Royhman
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago, Chicago, IL 60612, USA.
authors.forename: Cortino
authors.initials: C
authors.lastname: Sukotjo
authors.affiliation: Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA; Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL 60607, USA. Electronic address: takoudis@uic.edu.
authors.forename: Christos G
authors.initials: CG
authors.lastname: Takoudis
mesh_terms: D000497:Alloys; D008422:Materials Testing / Q000379:methods*; D056951:Photoelectron Spectroscopy; D014025:Titanium / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D017155:Wettability; D014961:X-Ray Diffraction
chemical_list: D000497:Alloys; D014867:Water; C031462:titanium alloy (TiAl6V4); D014025:Titanium
keywords: Sandblasted–acid etched Ti; Surface free energy; Ti-V alloy and Ti-II; TiO(2) atomic layer deposition; Water contact angle