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To investigate the effect of the ionic liquid (IL) chain length on the surface properties and photoactivity of TiO2, a series of TiO2 microspheres have been synthesized via a solvothermal method assisted by 1-methyl-3-octadecylimidazolium chloride ([ODMIM][Cl]) and 1-methyl-3-tetradecylimidazolium chloride ([TDMIM][Cl]). All as-prepared samples were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), scanning transmission microscopy (STEM) and the Brunauer–Emmett–Teller (BET) surface area method, whereas the photocatalytic activity was evaluated by the degradation of phenol in aqueous solution under visible light irradiation (λ > 420 nm). The highest photoefficiency (four times higher than pristine TiO2) was observed for the TiO2 sample obtained in the presence of [TDMIM][Cl] for a IL to TiO2 precursor molar ratio of 1:3. It was revealed that interactions between the ions of the ionic liquid and the surface of the growing titanium dioxide spheres results in a red-shift of absorption edge for the IL–TiO2 semiconductors. In this regard, the direct increase of the photoactivity of IL–TiO2 in comparison to pristine TiO2 was observed. The active species trapping experiments indicated that O2•− is the main active species, created at the surface of the IL–TiO2 material under visible-light illumination, and is responsible for the effective phenol degradation.

This paper presents the results of physical and chemical properties of zeolite - clinoptilolite (Z), on the basis of which its usefulness in different terms and applications was assessed. Same pozzolan was also investigated and analyzed in term of the changes that it causes in the system pozzolan - cement – lime - sand - water with different content of ingredients. In order to identify the hydration products in the natural conditions, infusion (80ºC) and autoclaving (180°C) XRD, DTA / TG and SEM was used. The results indicate that clinoptilolite is characterized by moderate pozzolanic activity and can be successfully used as a pozzolanic additive for cement, and a binder in the production of aerated concrete.