The surface characteristics of different carbon materials: activated carbon, carbon felt, glassy carbon and a porous carbon monolith were investigated. The specific surface area was examined by the BET method with N2 adsorption, the amount and the type of surface oxygen groups by Boehm titration as well as by temperature-programmed desorption (TPD). By comparing the results obtained using BET analysis with those of TPD and the Boehm method, it was found that the number of surface groups was not proportional to the specific surface area. The total amount of oxygen groups, obtained by TPD, is higher than the amount obtained by Boehm?s method for porous samples. The inconsistencies between these results originate from the fact that the Boehm method is limited to the determination of acidic and basic groups, whereas TPD provides information on the total number of all surface oxygen groups. In addition, the presence of porosity could reduce the solvent-accessible surface in the Boehm method. The TPD profiles of CO evolution showed the presence of a low temperature maximum, below 650 K, which originates from CO2 reduction on the carbon material surface.
TiO2/carbon composites were synthesized by hydrothermal carbonization, using titanium isopropoxide and glucose precursor solution to obtain composites with Ti/C molar ratios ranging from 0.05 to 0.30. Characterization of obtained composites was performed by thermogravimetric analysis, scanning electron microscopy, nitrogen adsorption–desorption isotherms, X-ray diffraction, UV–Vis diffuse reflectance spectroscopy and Fourier transform infrared spectroscopy. The possibility of using TiO2/carbon composites as photocatalysts for UV assisted degradation of methylene blue in aqueous solution and selected pharmaceuticals from multicomponent solution was examined. It was found that increase in the glucose concentration, i.e. increased carbon content, leads to the higher porosity and increase in the share of photocatalytically active anatase phase in obtained TiO2/carbon composites. Sample obtained from the most concentrated glucose solution (TiO2/HTC4), showed the superior photocatalytic activity under UV irradiation toward both methylene blue and selected pharmaceuticals. In addition, TiO2/HTC4 show high recycling ability with degradation ratio of methylene blue higher than 81% after five cycles. Also, TiO2/HTC4 is expected to be a promising candidate for photocatalytic processes using visible light