Defective Titania Photocatalyst Modified with Iron Oxides for Oxidative Decomposition of Organic Compounds

Abstract Ultrafine anatase titania of high crystallinity, composed of ≈10‐nm uniform particles, was prepared by a simple solvothermal method, without any additional heat treatment. Subsequently, the photodeposition method was chosen for the surface titania modification with different contents of iron. The properties of obtained samples were estimated by various methods, including, X‐ray diffraction, diffuse reflection spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive X‐ray spectroscopy, and transmission electron microscopy. Moreover, photoelectrochemical properties were investigated via measurements of photocurrent, electrochemical impedance and cyclic voltammetry. The photocatalytic activity was tested towards oxidative decomposition of acetic acid and different antibiotics from tetracycline (TC) group under UV and/or vis irradiation, including also scavengers’ tests. It was found that optimized conditions of solvothermal reaction allowed an easy control of samples’ properties. Interestingly, the bare titania sample exhibit vis activity (even at 550 nm) due to its defective structure, probably resulting from carbon species (dopants). The modification of titania with deposits of mixed iron oxides results in preparation of highly active samples at broad irradiation ranges, with a real possibility to replace noble metals as titania modifiers. It was also found that superoxide radicals were the main oxidative species under vis irradiation, suggesting the Z‐scheme mechanism.