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Titanium dioxide is a photocatalyst, known not only for its ability to oxidize organic contaminants, but also for its antimicrobial properties. In this article, significant enhancement of the antimicrobial activity of TiO2 (up to 32 times) was demonstrated after its activation by ball milling. The antimicrobial activity was analyzed for one fungal and 13 bacterial ATCC strains using the microdilution method and recording the minimum inhibitory concentration (MIC) values. In order to further investigate the correlation between the mechanical activation of TiO2 and its antimicrobial activity, the structure, morphology and phase composition of the material were studied by means of Electron Microscopy, X‐ray diffraction and nitrogen adsorption‐desorption measurements. UV‐Vis diffuse reflectance spectra were recorded and the Kubelka‐Munk function was applied to convert reflectance into the equivalent band gap energy (Eg) and, consequently, to investigate changes in the Eg value. X‐ray photoelectron spectroscopy was used to analyze the influence of mechanical activation on the Ti 2p and O 1s spectra. The presented results are expected to enable the development of more sustainable and effective advanced TiO2‐based materials with antimicrobial properties that could be used in numerous green technology applications.

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Copper selenide thin films of three different thicknesses have been prepared by vacuum evaporation method on a glass substrate at room temperature. The optical properties of the films were investigated by UV-VIS-NIR spectroscopy and photoluminescence spectroscopy. Surface morphology was investigated by field-emission scanning electron microscopy. Copper selenide exhibits both direct and indirect transitions. The band gap for direct transition is found to be ~2.7 eV and that for indirect transition it is ~1.70 eV. Photoluminescence spectra of copper selenide thin films have also been analyzed, which show emission peaks at 530, 550, and 760 nm. The latter corresponds to indirect transition in investigated material.

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In this paper, we describe synthesis and characterization of YVO 4 and Eu 3+doped YVO 4 nanopowders. Two methods of preparation were used-solution combustion synthesis (SCS) and classical ceramic method (CCM)-and compared. Morphology and structure of all samples were characterized with atomic-force microscopy (AFM), X-ray diffraction (XRD), and field-emission scanning electron microscopy (SEM). Raman spectroscopy was used to discuss the isotope-like effect. It is confirmed that doping with Eu ions results in a change of Raman spectra of doped samples-new modes arise, and intensity of existing ones change. Influence of different preparation methods on isotope-like effect is presented with detailed calculations of shifted modes.