Surface chemical analysis of photocatalytic wettability conversion of TiO₂ nanoparticle coating

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Milena Stepien, Jarkko J. Saarinen, Hannu Teisala, Mikko Tuominen, Mikko Aromaa, Jurkka Kuusipalo, Jyrki M. Mäkelä, Martti Toivakka
Publisher: ELSEVIER SCIENCE SA
Publication year: 2012
Journal: Surface and Coatings Technology
Journal acronym: SURF COAT TECH
Volume number: 208
Start page: 73
End page: 79
Number of pages: 7
ISSN: 0257-8972
eISSN: 1879-3347


Abstract

Surface chemical analysis of photocatalytic wettability conversion of the TiO2 nanoparticle coating is performed by the water contact angle measurement and X-ray photoelectron spectroscopy (XPS). It is observed that the UVA irradiation and heat treatment strongly affect on the water contact angle. Initially superhydrophobic TiO2 nanoparticle coated paperboard surfaces can undergo several transition loops between hydrophobic and hydrophilic states: the surface hydrophilicity can be induced by ultraviolet A (UVA) radiation whereas high temperature oven treatment results in superhydrophobic surface. The XPS spectra shows that UVA irradiation induces photocatalytic oxidation of the TiO2 nanocoated surface whereas the oven treatment decreases the amount of oxygen related to the hydroxyl groups. The wettability changes are related to the degree of hydroxyl groups or aliphatic chains present on the TiO2 surface. (c) 2012 Elsevier B.V. All rights reserved.


Keywords

Liquid flame spray process, Nanocoatings, Photocatalytic effect, Surface chemistry, Wettability

Last updated on 2019-16-09 at 05:52