Photocatalytic hydrogen evolution and Rifampicinum destruction over carbon-modified TiO2

Carbon-modified TiO2 using a sol-gel method (TiO2/C-SG) and mechanochemical treatment (TiO2/C-MC) was obtained. X-ray powder diffraction (XRD), scanning electron microscopy with an integrated system for electron microprobe analysis (SEM, EDX), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area analysis, X-ray photoelectron spectroscopy (XPS), Infrared (IR) and Ultraviolet-visible (UV-Vis) spectroscopy were applied for the powders characterization. The presence of a hysteresis loop in the nitrogen ad(de)sorption isotherms for the synthesized samples proved their mesoporous structure. XRD analysis revealed the anatase and rutile phase in TiO2SG with a size of 10 and 7 nm, respectively, and only anatase phase (15-16 nm) for all TiO2/C-SG samples modified by a sol-gel method was observed. Carbon additives to TiO2 did not lead to significant shifts in the peaks of bond energies of Ti 2p, O 1s and C 1s levels. The powders TiO2/C-SG had additional bands in IR-spectra which are characteristic bonds of carbon with oxygen unlike the TiO2/C-MC samples. It was found that modification of titanium dioxide with carbon by a sol-gel method leads to the band gap narrowing. Photocatalytic activity of the synthesized samples was investigated in H-2 photoproduction and Rifampicinum (RF) photodestruction. The TiO2/C-SG samples showed higher photocatalytic activity in both reactions compared to TiO2/C-MC. The correlation between the RF photocatalytic degradation degree and RF adsorption was demonstrated. The reusability of the powders in RF photodegradation was checked.