MBOClxBr1-x microspheres derived from Bi-MOF for efficient degrade tetracycline hydrochloride under visible light irradiation

Through the halogenation reaction and employing metal-organic framework microspheres (Bi-MOF-M) as a sacrificial template, interleaved BiOCl x Br 1-x nanosheet layers were grown on its surface. In contrast to Bi-MOF-M, the acquired MBOCl x Br 1-x not only extends the visible light absorption range but also facilitates the effective separation of photogenerated carriers . Furthermore, based on Density Functional Theory simulation, the band gap structure of MBOCl x Br 1-x could be effectively adjusted by changing the molar ratio of Cl/Br, which aligned with the results of Tauc plots. Taking tetracycline hydrochloride (TCH) as the target pollutant, we evaluated the photocatalytic degradation activity, stability, and recyclability of the sample under visible light. It was observed that materials with varying Cl/Br molar ratios significantly influenced the photocatalytic degradation of TCH, with MBOCl 0.25 Br 0.75 exhibiting the highest photocatalytic activity , the degradation efficiency reached 83.16 %, and the kinetic constants for TCH degradation were found to be 5.7 times and 1.5 times greater than those of Bi-MOF-M and BiOCl 0.25 Br 0.75 , respectively. Additionally, Rhodamine B (RhB), oxytetracycline (OTC), ciprofloxacin hydrochloride (CIP·HCl), methylene blue (MB), and malachite green (MG) were employed as extended contaminants to further assess the catalytic activity of the samples. We also investigated the effects of pH, inorganic anions , and temperature on the degradation of TCH by MBOCl 0.25 Br 0.75 . The potential pathways for the photocatalytic degradation of TCH by the catalyst were elucidated through high-performance liquid chromatography-mass spectrometry analysis. Meanwhile, a rational mechanism for the photocatalytic degradation of TCH by the MBOCl 0.25 Br 0.75 catalyst with ·OH and ·O 2 - as the predominant active species was proposed. A green synthesis method had been proposed that not only preserves the exceptional structural properties of metal-organic frameworks (MOFs) but also modulated the energy band structure and enhances photocatalytic performance. • MBOCl x Br 1-x achieved high removal efficiency of TCH (83.16%) under visible light. • MBOCl 0.25 Br 0.75 exhibited good structural stability and can effectively degrade TCH at room temperature. • The band gap structure of MBOCl x Br 1-x could be effectively adjusted by changing the molar ratio of Cl/Br, thereby increasing the material's absorption of visible light. • MBOCl 0.25 Br 0.75 displayed excellent photocatalytic properties for a variety of pollutants.