Institute of Chemistry of Far Eastern Branch of Russian Academy of Sciences, Vladivistok, Russia:

V. V. Zheleznov, Leading Researcher, e-mail: zheleznov_sergey@mail.ru
Yu. V. Sushkov, Engineer
S. A. Sarin, Junior Researcher
E. I. Voyt, Senior Researcher

Nanostructured microtubes of the composition TiO₂/ZrO₂/SiO₂ with a variable content of zirconium oxide (from 0 to 27 wt. %) were synthesized by the template sol-gel method. The activated carbon fiber was used as template. The materials were synthesized using two sets of precursors: TiCl₄, ZrOCl₂ and Ti₂(SO₄)₃, ZrO(NO₃)₂. The dependence of the materials morphology and structure on the synthesis conditions was investigated by scanning electron microscopy (SEM), small-angle X-ray scattering (SAXS), and Raman spectroscopy. The samples structure and morphology depend on the Zr-dopant content to a greater extent than on the treatment temperature (550–850 ^oC). The increased content of the Zr-dopant (higher than 5.2 wt. %) results in redistribution of the Ti/Zr oxide ratio and is accompanied with destruction of microtubes. Differences in the morphology of obtained microtubes using chloride and sulfate precursors are related to the ratio between sizes of colloid particles in initial solutions and those of template mesopores.
Synthesis and investigation of morphology and structure of materials were carried out within the program of fundamental scientific investigations RAS (project No. 0265-2014-0001).

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