Ultrahigh ciprofloxacin accumulation and visible-light photocatalytic degradation: Contribution of metal organic frameworks carrier in magnetic surface molecularly imprinted polymers

Pharmaceuticals pollutions causes inevitable threat for both water environment and human health. However, both the selective and efficient accumulation together with degradation in real wastewater is still one of the major challenges which need further exploration. Here, we designed and synthesized MIL-100 based mesoporous carries supported surface molecularly imprinted polymers. The functional monomer was successfully grafted on the metal organic frameworks (MOFs) carries with magnetic core (Fe₃O₄). The simultaneous hydrolysis of functional precursor and condensation of the hydrolyzed precursors form a three–dimensional polymer network. Thanks to the high surface area and abundant mesoporous channels formed by the fast microwave irradiation method, it can facilitate mass transfer process and achieve high uptake capacity. This MIL-100 based imprinted polymer showed both ultrahigh selectivity (α_(QMIP/QNIP) = 3.54) and highest uptake capacity calculated by the Langmuir equation (273.65 mg/g) for Ciprofloxacin so far. In order to prove the role of MIL-100 insides, pore size distribution, surface area, high angle annular dark field-scanning transmission electron microscopy (HAADF–STEM) images were studied detailly. Adsorption mechanism have been proposed based on X-ray Photoelectron Spectroscopy (XPS) and Infrared Spectroscopy (IR) spectra before and after the treatment. Importantly, the influence of environmental competitors including the inorganic ions and natural organic matters have been evaluated separately. Furthermore, the material can effectively remove targeted compound which was spiked in real secondary effluents from Beijing, substantiating that this novel MOFs–based material is among the rank of excellent CIP adsorbent. Furthermore, the iron-based active sites can be accessible for CIP, resulting the completely degradation under visible − light irradiation with small amount of hydrogen peroxide added. Our study presents a facile approach by introducing MILs to improve the performance of imprinted polymers.