Efficient synthesis of multifunctional α-Fe2O3 QDs/TS-1 as an artificial nanozyme for simultaneous colorimetric detection and photodegradation of tetracyclines

In this study, a multifunctional catalyst was developed innovatively by loading α-Fe2O3 quantum dots (QDs) onto Titanium Silicalite-1 (TS-1), creating an artificial nanozyme capable of simultaneously detecting, adsorbing, and photodegrading tetracyclines (TCs) in water. The catalyst demonstrated a limit of detection (LOD) as low as 19.7 μg/L for oxytetracycline (OTC), 23.1 μg/L for doxycycline (DOX), and 35.9 μg/L for tetracycline (TC). The peroxidase-mimic activity of the nanozyme, which was enhanced by TCs and caused a visible color change in 3,3′,5,5′-tetramethylbenzidine (TMB), was thoroughly investigated using DFT calculations. Additionally, the artificial nanozyme exhibited exceptional adsorption capabilities and photocatalytic activity under solar light irradiation, achieving a total removal rate of about 70 %. The underlying mechanism was also studied. This research provided valuable insights for the scalable production of multifunctional catalysts, thereby advancing the practical application of "integration of diagnosis and treatment" strategies for managing and controlling TCs in the environment.