Location-Controlled Synthesis of Hydrophilic Magnetic Metal-organic Frameworks for Highly Efficient Recognition of Phthalates in Beverages

MOF-modified magnetic composites have become a burgeoning star in modern materials science. However, most of these MOF-modified magnetic composites are prepared by physical deposition of MOFs on the surface of magnetic particles, causing the MOFs layer nonuniform and unstable, which largely discounts the potential performance of such fuctional materials. In this work, we proposed a location-controlled strategy for functionalization of hydrophilic magnetic graphene by ZIF-8 MOF to construct uniform and robust nanosheets (magG@PDA@ZIF-8). In this synthetic protocol, PDA provides not only excellent water dispersion, but also serves as a potential coordination site for Zn2+ chelation, which establishes site-specified chemical bonding between ZIF-8 MOF and matrix. The obtained nanosheets hold regular porous structure and large surface area with unique pi-pi stacking electron system, strong magnetism and excellent water dispersibility. Chemically bonded structure contributes to the enhanced performance of the resulting magnetic composites in terms of stability, reliability and recyclibiity, when magG@PDA@ZIF-8 is used to enrich 9 PAEs in real cola samples.