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New composites consisting of decahedral anatase particles exposing {0 0 1} and {1 0 1} facets coupled with accordion-like layered Ti3C2 with boosted photocatalytic activity towards phenol and carbamazepine degradation were investigated. The photocatalysts were characterized with X-ray diffraction (XRD), diffuse reflectance spectroscopy (DR/UV–Vis), Brunauer-Emmett-Teller (BET) specific surface area, Raman spectroscopy, scanning electron microscopy (SEM), electron paramagnetic resonance (EPR) spectroscopy, emission spectroscopy, luminescence decay analysis, electrochemical impedance spectroscopy (EIS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and electrophoretic mobility measurements. The effect of hydrothermal reaction parameters on physicochemical, structural, and photocatalytic properties was studied. In all photodegradation processes, ortho-hydroxyphenol and para-hydroxyphenol were detected as the first intermediates of phenol decomposition. For the TiO2/Ti3C2(140,12) sample containing VTi, a higher concentration of para-hydroxyphenol than ortho-hydroxyphenol was observed, whereas for sample TiO2/Ti3C2(220,24) higher concentration of ortho-hydroxyphenol was noticed. The formation of surface heterojunction between {1 0 1} and {0 0 1} facets of decahedral anatase particles grown on Ti3C2 surface led to improved photoelectron transfer and enhanced photocatalytic activity towards degradation of carbamazepine - non-biodegradable and susceptible to bioaccumulation in living organisms commonly used pharmaceutical agent. Moreover, modification of TiO2/Ti3C2 surface with iron by magnetron sputtering deposition markedly improved photocatalytic activity in carbamazepine decomposition, with nearly 100% degradation in 60 min of irradiation under simulated solar light.

In this study, special attention is focused on the design of TiO2 morphology and microstructure in the two-step preparation procedure using TiOF2 as a precursor to study their photodegradation mineralization efficiency. Firstly, TiOF2 was synthesized by a simple solvothermal method using titanium(IV) tetrafluoride, which was further used as a precursor in preparation of anatase 2D nanosheets, octahedral, decahedral, and rectangular prisms shape structures. The as-obtained nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area analysis (BET), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. It was assumed that TiOF2 could be applied as a useful precursor for the preparation of nanostructured TiO2 with defined morphology. Simple controlling of the reaction environment, together with the stabilizing effect of the introduced substrates, resulted in the formation of TiO2 particles with different morphologies and consequently exposed crystal facets. The presence of {0 0 1}, {1 0 1} and {1 0 0} facets influence on their photocatalytic activity but mostly on their mineralization efficiency and the pathway of phenol degradation. From the obtained series, the TiO2 octahedra exposing {1 0 1} facets exhibited the highest photoactivity and mineralization efficiency under UV–Vis light irradiation, which decreases as the other facets appear and become more exposed. The obtained results were compared with a computational study on the ∙OH and ∙O2– attack on the phenyl ring. Overall results showed that the surface effects of the photocatalyst could be an influencing factor in both mineralization efficiency and photodegradation products formation.