Efficient photocatalytic degradation of tetracycline hydrochloride by Fe-TiO2/MIL-101(Cr) nanocomposites under visible light

The misuse of antibiotics, including tetracycline hydrochloride (TCH), can easily lead to drug resistance and the decline of human immunity, which is extremely harmful to human health. In this paper, TiO2 was modified using two different techniques: semiconductor composite and metal ion doping. Fe-TiO2/MIL-101 (Cr) nanocomposite photocatalyst (FTM-x) was effectively prepared by solvothermal method and used for the degradation of TCH in water under visible light. The performance of ternary composite materials, in comparison to single or binary compounds, are improved by using an easy and convenient hydrothermal technique. Among them, FTM-2 showed efficient photodegradation and structural stability. After 120 min in visible light, FTM-2 removed 95.5 % of TCH, and the removal was maintained at 85 % after 4 cycles. The composite FTM-x was characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Raman, which proved the successful synthesis of the composite. Photoelectrochemical and photoluminescence (PL) analyses were used to examine the photoelectric properties of the prepared photocatalysts. The results suggested that optimizing the composites' photoresponse and electron-hole separation could be linked to improving the photocatalytic performance. The photocatalytic activity of superoxide radicals (center dot O2-) and hydroxyl radicals (center dot OH) was demonstrated to be mediated by free radical trapping investigations, which were utilized to determine the active components of the process.