Titanate nanofunnel brushes: toward functional interfacial applications

Abstract

Titanate nanofunnel brushes were grown on sol-gel derived amorphous TiO(2) thin films, whose shape can be tuned from nanosheets to nanofunnels by changing hydrothermal conditions. A superhydrophobic adhesive surface was achieved by a chemical modification of the brushes.

Superhydrophobic adhesive surface on titanate nanotube brushes through surface modification by capric acid

“…TNT brushes are a promising material for many types of interfacial applications because of their aligned nanostructures and the finely controllable surface of individual TNTs thanks to abundant hydroxyl groups. The TNT brushes for surface modification by capric acid in the present paper were prepared by the same method as we reported previously [19]. Figure 1 shows SEM images of the obtained TNT brushes, which evenly grew on the amorphous TiO 2 precursor film (Fig.…”

“…It has been difficult to use TNTs for such interfacial applications because TNTs are generally entangled without orientation through strong hydrogen bonds. We have recently reported on the formation of vertically aligned TNTs (TNT brushes) on a sol-gel-derived amorphous TiO 2 film [18,19]. TNT brushes are a promising material for many types of interfacial applications because of their aligned nanostructures and the finely controllable surface of individual TNTs thanks to abundant hydroxyl groups.…”

“…TNT brushes were prepared via a hydrothermal treatment of sol-gel-derived amorphous TiO 2 films deposited on 1.5 cm 9 1.5 cm rutile TiO 2 plates using the method described in our previous reports [19,23]. The TiO 2 coating sol was prepared by the following process [31].…”

“…The obtained TNTs are entangled and without any preferential orientation [17]. Recently, we have successfully synthesized vertically oriented TNTs on a precursor film surface ('TNT brushes') [18,19]. The use of sol-gel-derived amorphous TiO 2 films as a precursor instead of TiO 2 powder and the milder conditions of the hydrothermal synthesis method induced heterogeneous nucleation on the surface of the precursor film, which resulted in the formation of TNT brushes on the TiO 2 film.…”

“…The use of sol-gel-derived amorphous TiO 2 films as a precursor instead of TiO 2 powder and the milder conditions of the hydrothermal synthesis method induced heterogeneous nucleation on the surface of the precursor film, which resulted in the formation of TNT brushes on the TiO 2 film. These TNT brushes can then be surface modified to achieve a superhydrophobic adhesive surface [19]. Superhydrophobic adhesive surfaces can be a useful tool for advanced functional applications such as microfluidic devices [20], water manipulation [21][22][23], and oil/water separation [24].…”