title: ToF-SIMS analysis of UV-switchable TiO2-nanoparticle-coated paper surface.
abstract: The chemical composition of a TiO2 nanoparticle coated paper surface was analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS) to study the interconnection between wettability and surface chemistry on the nanoscale. In this work, a superhydrophobic TiO2 surface rich in carboxyl-terminated molecules was created by a liquid flame spray process. The TiO2 nanoparticle coated paper surface can be converted by photocatalytic oxidation into a highly hydrophilic one. Interestingly, the hydrophilic surface can be converted back into a superhydrophobic surface by heat treatment. The results showed that both ultraviolet A (UVA) and oven treatment induce changes in the surface chemistry within a few nanometers of the paper surface. These findings are consistent with those from our previously reported X-ray photoelectron spectroscopy (XPS) analysis, but the ToF-SIMS analysis yields more accurate insight into the surface chemistry.
authors: Laboratory of Paper Coating and Converting, Center for Functional Materials, Abo Akademi University, Porthansgatan 3, FI-20500 Åbo/Turku, Finland. milena.stepien@abo.fi
authors: Milena
authors: M
authors: Stepien
authors: Jarkko J
authors: JJ
authors: Saarinen
authors: Hannu
authors: H
authors: Teisala
authors: Mikko
authors: M
authors: Tuominen
authors: Mikko
authors: M
authors: Aromaa
authors: Janne
authors: J
authors: Haapanen
authors: Jurkka
authors: J
authors: Kuusipalo
authors: Jyrki M
authors: JM
authors: Mäkelä
authors: Martti
authors: M
authors: Toivakka