Nano Seminar
Thursday, 8. 4. 2021, 14.00,
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Tereza Václavů
Department of Condensed Matter Physics,
Faculty of Mathematics and Physics, Charles University, Czech republic
Thermal stability of titanate nanotubes
Study of temperature stability of titanate nanotubes (Ti-NT) is important because applications of Ti-NT such as solar cells or photocatalysis (and others) require heating of the material [1]. By heating of Ti-NT at low temperature range (from room temperature till approximately 200o C) the releasing of the adsorbed and interlayer water were observed by X-ray diffraction [2], [4] and DSC analysis [3], [5]. At higher temperature the anatase structure of TiO2 started to grow [4],[5]. Finally at the temperatures higher than 700o C the nanotubes transformed to nanorods with the structure: Na2Ti6O13 [2],[3],[4],[5] and nanoparticles with rutile structure of TiO2 [4],[5].
In this contribution, the structure changes of titanate nanotubes were studied by combination of powder X-ray diffraction and DSC analysis. At low temperature the releasing of water were observed by X-ray diffraction and confirmed with DSC. The next transformation to anatase structure of TiO2 started approximately at 520o C which was observed by powder X-ray diffraction and with increasing temperature the anatase structure became more crystalline. DSC showed that this transformation occurred at a little bit higher temperature of 550o C. The final transformation to nanorods with structure of Na2Ti6O13 and nanoparticles with rutile structure of TiO2 was started at 750o C and with increasing temperature the powder X-ray signal of these two phases became stronger and the anatase structure was completely transformed to rutile.
References:
[1] Bavykin DF. V.,Walsh F. C.: RSC Publishing, 2010.
[2] Nikolic L. M., Maletin M., Ferreira P., and Vilarinho P. M.: Processing and application of ceramics, 2, 2008.
[3] Yu D.-N., Liu W.-X., Ma J., Qu X.-G., Cao W.-B., Zhang Z./Y., and Mao J.-H.:. Material Science Forum, 620-622, 2009.
[4] Yoshida R., Suzuki Y., and Yoshikawa S.: Materials chemistry and physics, 91, 2005.
[5] Morgado E., jr, de Abreu M. A. S., Pravia O. R. C., Marinkovic B. A., Jardim P. M., rizzo R.C., Araujo A.S.: Solid State Science, 8, 2006
*corresponding author: e-mail:
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