Among all nanostructured materials, nanofibers represent a unique subgroup, which represents
an important area of research and a potential solution to the current problems in several fields.
The variety of materials and production methods that can be used to form nanofibers and easily
adjust their properties additionally increases their value. Titanium-based, especially titanium
dioxide (TiO2) and titanium oxynitride (TiON), have so far been successfully applied in
electrochemical, biomedical and pharmaceutical field. Therefore, the aim of this Master’s thesis
was to produce titanium-based inorganic nanofibers and evaluate their properties and
consequently their use in applied fields.
Our first step was to optimize polymer solutions and the electrospinning method itself, with the
goal of developing single-layer and double-layer nanofibers as well as multi-layer nanofiber
mats. Optimization consisted of varying the content of polymer (polyvinylpyrrolidone (PVP)
or polyacrylonitrile (PAN)), precursor of TiO2 (titanium (IV) isopropoxide (TIP)) and additives
(acetic acid) in suitable solvent (N,N-dimethylformamide (DMF) and ethanol). In order to
prepare catalytically active nanofibers, solutions with nickel salt were also prepared and
optimized. Selected samples were further calcinated in an ammonia atmosphere to produce
TiON nanofibers or in an inert atmosphere to produce TiO2 nanofibers. Morphology and
elemental composition of prepared nanofibers were investigated by scanning electron
microscopy and energy dispersive spectroscopy. Furthermore, we used various electrochemical
methods to analyze the catalytic properties of selected nanofiber samples and different methods
to analyze their antibacterial activity against Escherichia coli TOP10.
We found that a successful development of nanofibers TiON or TiO2 requires a higher amount
of acetic acid compared to TIP and that a higher amount of polymer results in a higher diameter
of nanofibers. Preparation of PAN nanofibers is possible only from DMF. Although nanofibers
TiON are not catalytically active on their own, we concluded a potential of their use in catalysis
in the form of multi-layer nanomaterials with additionally included catalysts. Results of
antibacterial activity analyzes were also promising, as a reduced metabolic activity of bacteria
and an inhibition of their growth were detected. With this we have confirmed the potential for
the use of this type of nanofibers both in the field of electrocatalysis and for the purpose of
inhibiting the growth of bacteria.
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