Novel ACr2O4 (A = Mg, Cu, Ni)/MIL-101(Cr) photocatalysts: Synthesis, characterization, performance prediction and applications for the photo–degradation of tetracycline hydrochloride

Abstract

The Z-scheme ACr₂O₄ (A = Mg, Cu, Ni)/MIL-101(Cr) heterojunction photocatalysts have been synthesized by a simple method. By means of phase structure, microstructure and composition analysis, it was determined that the ACr₂O₄ (A = Mg, Cu)/MIL-101(Cr) photocatalysts only contained the target component, while the NiCr₂O₄/MIL-101(Cr) photocatalyst also contained a small amount of Cr₂O₃ impurities. The photocatalytic experiments showed that the degradation percentage of MgCr₂O₄/MIL-101(Cr) photocatalyst reached 78 % when the mass percentage of MIL-101(Cr), the catalyst content, the initial tetracycline hydrochloride concentration, pH value and illumination time were 10 %, 1 g/L, 50 mg/L, 7 and 120 min, respectively. The neural network model can effectively predict the photocatalytic activity of MgCr₂O₄/MIL-101(Cr) photocatalyst. Various characterization confirmed that the holes, hydroxyl radicals and superoxide radicals are the main active species involved in photocatalytic degradation of tetracycline hydrochloride. This research will provide experimental basis and theoretical support for exploring the construction of new metal–organic framework (MOF) based heterojunction photocatalysts.