The simultaneous detection and removal of organophosphorus pesticides by a novel Zr-MOF based smart adsorbent

Developing a smart adsorbent that can efficiently detect and remove toxic organophosphorus pesticides is important but still a great challenge. Here, a novel MOF-based smart adsorbent, Fe3O4@SiO2@UiO-67, was successfully fabricated via a versatile layer by layer assembly strategy and applied to the simultaneous selective recognition, detection and removal of glyphosate. The prepared smart adsorbent contains Zr-OH groups with high affinity for phosphate groups, endowing it with selective recognition and a higher adsorption capacity for glyphosate. Moreover, combining it with glyphosate leads to changes in the fluorescence intensity of the smart adsorbent, and incorporating silica impedes electron transfer between UiO-67 and the magnetic core, which can lead to the identification of the adsorbate and its concentration, and achieve a lower detection limit. Furthermore, using Fe3O4 as the magnetic core of the smart adsorbent facilitates the separation and removal process via an external magnetic field. Under optimized conditions, the obtained smart adsorbent exhibits excellent detection and adsorption performance with a high adsorption capacity (256.54 mg g(-1)), good reusability, and a low detection limit (0.093 mg L-1) for glyphosate, implying that the smart adsorbent has integrated the advantages of the individual components. All of this indicates that MOF-based smart adsorbents are promising for synchronous adsorption/detection and the removal of OPPs, presenting a viable option for monitoring water quality and treating wastewater.