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Titanium dioxide in the form of anatase is known to be a good photocatalyser but catalytic properties strongly depend on TiO2 grain size, morphology and surface area of thin film. The aim of this study was to evaluate influence of carbon nanotube additive on photocatalitic properties of TiO2.Titanium dioxide/multiwalled carbon nanotubes (MWCNT) nanocomposites were prepared by sol-gel method in the form of a thin layer on glass substrates. Samples were characterized by X-ray diffraction (XRD) and Grazing Incidence Diffraction (GID), Raman, FTIR and UV-VIS spectroscopy, as well as scanning electron microscopy (SEM). The photocatalytic activity of prepared films was evaluated by the detection of changes in the UV-VIS spectra after the discoloration of Reactive Black V pigment - water solution. It was found that the crystalline TiO2 is composed of anatase phase only. Presence of MWCNTs in the composite increases the size of TiO2 particles. Additive of nanotubes into the TiO2 resulted in an increase in photocatalytic activity in both the UV and visible range by 10 and 50% respectively compare to undoped TiO2. Furthermore, carbon nanotubes lead to better dye adsorption on the surface. Additionally significant reduction in the contact angle, approximately 50% (compare to pure TiO2) was also observed. The obtained results suggest that the TiO2/carbon nanotubes composite material can be activated by light from visible range.

The work was focused on the spectroscopic examination of zirconia-based layers deposited on metallic substrates. Metallic biomaterials belong to the group of well-known and most widely applied materials in medicine. They might be characterized by the easiness of formation and good mechanical properties. However, the surface properties of the material need to be strictly controlled to prevent corrosion processes and ensure biocompatibility. One of the modifications leading to improvement of the properties important in terms of considering the material for biomedical applications was the fabrication of ceramic layers on the surface. Presented zirconia-based layers doped with calcium and hydroxyapatite were obtained using the sol-gel method and deposited on the metallic (titanium and steel) surface with the use of dip-coating technique and electrophoretic deposition (EPD) method. Obtained layers were examined with multiple spectroscopic and microscopic methods such as Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Also the surface properties – wettability and surface free energy (SFE) – were measured. Bioactivity of the obtained layers was evaluated by the in vitro test in simulated body fluid (SBF) - the so-called Kokubo test.

The main objective of this paper is to attempt to determine the structure of free carbon phase in SiOC glasses derived from ladder-like silsesquioxane precursors. The samples were fired in argon flowing atmosphere, in a wide temperature range (200–800° C). Conducted XRD, Raman, MIR spectroscopy research allowed to determine the structure of obtained materials. Combined XPS and Raman studies enabled to establishing the point of formation of free carbon in silicon oxycarbide matrix. Two most popular concepts were confronted with Raman and XPS results of free carbon phase in studied materials. This allowed to conclude that for temperatures below 800 °C carbon is present in a form of graphite domains inside glassy matrix.

Structural changes accompanying stabilization and carbonization processes of the two types of polyacrylonitrile (PAN) nanofiber precursors (pure PAN and PAN with carbon nanotubes) were studied using infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The fibrous membranes were preliminary stabilized in air followed by the two-step carbonization process under nitrogen atmosphere. IR absorption spectra showed that the introduction of a small amount of functionalized multiwall carbon nanotubes (MWCNT) into the PAN precursor has a significant impact on its stabilization process. Raman spectroscopy study showed that the structure of carbon nanofibers containing CNT is distinctly more ordered in comparison to pure carbon nanofibers. Based on the XPS analysis the concentration of heteroatoms and the type and amount of functional groups on the surfaces of both types of nanofibers were determined. The results indicate a high potential of functionalized MWCNT as a pyrolysis modifier of polymer precursor leading to the formation of carbon nanofibers with controlled structure and defined chemical state of the surface.

Hybrid glasses based on tetraethoxysilane (TEOS) modified by addition of selected cyclosiloxanes have been prepared by sol–gel method. Octamethylcyclotetrasiloxane (D4) and 2,4,6,8-tetramethyl-2,4,6,8-tetravinylsiloxane (VMC) have been chosen as an organic modifier of the silica matrix. Molar ratio of TEOS to cyclosiloxane varied from 1:0 to 1:0.5. Structure of prepared hybrids has been studied by infrared spectroscopy (FTIR), photoelectron spectroscopy (XPS) and nuclear magnetic resonance spectroscopy (NMR). Optical properties of bulk glasses in the visible range have also been reported.

Hybrid glasses based on tetraethylorthosilicate (TEOS)–trimethoxyoctylsilane (TMOS) and TEOS–tetraethylorthotitanate (TEOT)–trimethoxyoctylsilane systems were prepared by sol–gel technique. Structure of the hybrids was studied by FTIR and XPS spectroscopy. The studies reveal that the titanium is mainly in tetrahedral coordination substituting for silica and acting as a glass former. Some part of titanium is also present in octahedral coordination. Optical properties of hybrid glasses in the visible range strongly depend on amount of organic modifier and higher transparency is observed for glasses having higher content of TMOS.

The results of structural studies of the glasses from Li2O–Bi2O3–PbO system were presented. Infrared spectroscopy (FTIR) and photoelectron spectroscopy (XPS) were applied to determine main structural unites and chemical composition of near-surface region. Glasses from the studied system are build up with lead in tetrahedral coordination and bismuth in octahedral coordination. Structural role of lithium relies on compensation of the electric charge and on separation of lead-reach and bismuth-reach regions preventing crystallization of the glasses. It was shown that the lithium is not present in near-surface regions. The thermal stability of the glasses was determined from DTA measurements. Optical properties in UV–vis region were also presented.

Isotope substitution method was used to identify the Li–O absorption bands in crystalline lithium silicates (2Li 2 O 3 ·SiO 2 , Li 2 O·SiO 2 , Li 2 O·2SiO 2 ) and selected aluminosilicates (β-eucriptite and β-spodumene). Isotopic shift was established after mathematical decomposition of the IR spectra. Absorption bands connected directly with internal, LiO 4 tetrahedron vibrations are observed in the range 460–250 cm −1 . Bending vibrations of Si–O–Li bridges give absorption bands in the range 500–600 cm −1 . The exact position of the bands and their isotopic shifts are given.

MIR spectra of lithium silicates and aluminosilicates were measured and compared with the simulated spectra. Simulation was carried out by mathematical summation of appropriate glass spectra taken in the right proportion. It was shown that the spectra obtained in this way are very similar to the measured spectra. It confirms phase inhomogeneity of studied glasses with short or even medium range of order. Structures of lithium silicate and aluminosilicate glasses consist of structural elements resulting from its composition and position in the field of primary crystallisation. The structure of these elements is very similar to their crystalline analogues with the same chemical composition, but they are much more disordered and do not have translation symmetry.

The glassy state of matter, in contrast to crystalline solids, is characterized by a lack of long-range order. In the structure of glasses, the bond lengths and bond angles are not fixed. As a consequence the vibrational spectra of glassy sustances exhibit various band shapes. The bands in these spectra are characterized by complex shapes and significant widths resulting in difficulties in the determination of the main spectral parameters, such as the number of bands, their positions and intensities. These difficulties limit the application of vibrational spectroscopy in the study of the structure of glasses. The main goal of the present work is to show that an appropriate procedure of decomposition of the complex bands in the spectra makes it possible to obtain important information on the structure of solid glassy substances. The procedure proposed is based on (a) minimization of the number of bands, and (b) comparison with the spectra of crystalline analogues. The number of components in a complex band and its parameters are found by analysis of the second derivative of the spectrum, using Fourier self-deconvolution as proposed by Griffiths and Pariente (Trends Anal. Chem., 5 (1986) 209). According to the procedure proposed, the spectra of the crystalline and glassy analogues of the following substances were decomposed: SiO2 (silica), K[AlSi2O6] (leucite) and Li(AlSi2O6) (spodumene). This decomposition of the complex bands in the spectra of glassy substances meant that their structures could be more readily deduced. It was shown that as well as the bands corresponding to the crystalline analogues in the spectra of glasses, there are bands responsible for characteristic features of the structure of glasses.