The diploma thesis was written on the basis of theoretical and experimental data obtained in previous research and our own research. At the same time, we wanted to confirm a partial hypothesis about the photocatalytic properties from the previous work, where colloidal solutions $TiO_2-SiO_2$ with different contents of doped vanadium were studied. The photocatalytic properties themselves have not been defined in more detail.
I prepared thin films from the synthesised working sols with different vanadium contents using the dip-coating technique. The most suitable withdrawal speed for lifting the glass slide from the sol that we chose was 20 cm/min.
The main focus of the research was to optimise the technique of thin film deposition of a fatty impurity used to determine the photocatalytic properties of the influence of vanadium. Initially, I tried using methyl stearate, but stearic acid offered better traceability. After successful optimization, I was able to continue the work with stearic acid and determine the photocatalytic properties of samples with different vanadium content.
The optical, structural and morphological properties of the photocatalyst samples were determined by X-ray powder diffraction (XRD), UV-Vis spectroscopy, photoluminescence, FTIR-ATR spectroscopy and scanning electron microscopy. The photocatalytic properties were initially determined by measuring the contact angle. However, we later decided to use FTIR-ATR spectroscopy because this technique provided better resolution and gave more repeatable results.
The results showed that the effect of increasing vanadium content reflects the expected higher absorption of visible light, but the increased vanadium content is mostly not reflected in improved photocatalytic properties.
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