Investigation of titanate nanotube-carbon nanotube composite layers by electron microscopy
Mária Darányi, Ákos Kukovecz, Zoltán Kónya, Imre Kiricsi
Department of Applied and Environmental Chemistry, University of Szeged,
Rerrich B. tér 1, Szeged, H-6720 Hungary
Titanium oxide (TiO2) is intensely researched today because of its advantageous
physical and chemical properties. TiO2 is widely used for various applications such as gas
sensors or solar cells and it is the most frequently investigated photocatalyst for the
degradation of pollutant chemicals.
The photocatalytic effect can be improved either by tuning the band structure or by the
prevention of the recombination of electron-hole pairs. Various carbon materials such as
multi-walled carbon nanotubes (MWCNT) can prevent the recombination. In addition,
MWCNTs can act as effective adsorbents as well [1].
We created titanate, anatase and anatase-MWCNT thin films by dip coating techniques
using titania nanoparticles of various shapes. The photocatalytic degradation efficiency of the
layers was evaluated by using methyl orange as a probe molecule. The film morphology was
followed by scanning electron microscopy (Fig. 1. and 2.).
Fig.1. Calcined titanate-MWCNT layer
Fig. 2. Degussa P25–MWCNT layer
We conclude that MWCNTs increase the photocatalytic efficiency of the layers. In
addition, the effect of MWCNTs depends on the titanate particle shape and the thickness of
the layer.
[1]H. Wang, H-L. Wang, W-F. Jiang, Z-Q. Li, Water Research, 2009, 43, 204.