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Competitive adsorption of complex nonsteroidal anti-inflammatory drugs (NSAIDs) from wastewater often reduces the adsorption capacity of object pollutants on most porous materials. To address this issue, NSAIDs molecules were proposed for engineering imprinted pores in UiO-66s to boost their adsorption capacity towards diclofenac sodium (DCF) and Cu(II) in a complex solution. Naproxen (NAP) with proper chemical structure was proved to introduce more imprinted pores (at ~19 A) with enhanced mesoporous volume, abundant unsaturated metal sites, and terminal hydroxyl groups in UiO-66@NAP. These new intriguing properties awarded high adsorption affinity to UiO-66@NAP for DCF and Cu(II), and their adsorption capacities reached up to 385 and 52 mg/g for single DCF and Cu(II) components, respectively. When DCF and Cu(II) simultaneously appeared in an aqueous solution, DCF was proved to preferentially occupy adsorption sites on UiO-66@NAP with higher adsorption kinetics compared to Cu(II). Afterwards, these pre-adsorbed DCF acted as new adsorption sites to bridge more Cu(II) in the solution. Similarly, the adsorbed Cu(II) on UiO-66@NAP had the same reciprocal bridging effect towards DCF, which realized the synergistic adsorption of DCF and Cu(II) over UiO-66@NAP. Notably, DCF was found to greatly boost the synergistic effect of the Cu(II) adsorption. As a result, UiO-66@NAP exhibited 1.5 and 2.6 times higher uptakes for DCF (573 mg/g) and Cu(II) (135 mg/g) in the binary system compared to their single pollutant system, and its equilibrium adsorption capacity was much higher compared to several state-of-the-art adsorbents. The current work set out a new strategy to modify MOFs for enhanced adsorption of complex NSAID contaminants and revealed a deep understanding of the interactions between NSAIDs and heavy metals ions.

Cu2O/MIL(Fe/Cu) composite was fabricated via an in-situ Cu-bridging strategy to enhance interfacial synergistic effect of photo-Fenton catalysis for thiacloprid (TCL) degradation. Characterization results showed that: (1) Cu2O was proved to grow on the surface of MIL(Fe/Cu) in Cu2O/MIL(Fe/Cu) composite and display a high BET surface area of 1553 m2/g; (2) Cu2O/MIL(Fe/Cu) reduced band gap from 2.5 to 1.3 eV and extended absorption from UV to visible region; (3) Cu-bridge was proved to promote the intimate interface between Cu2O and MIL(Fe/Cu), which accelerated charge transferred and shortened the binding gap and the reaction pathway from photo-induced electrons to Fenton-generated radicals. As a result, this boosted the redox reaction of Fe2+/Fe3+ and promoted the reversible degree of this catalytic redox ability of MIL(Fe). Catalytic performance exhibited that (1) Cu2O/MIL(Fe/Cu) showed a fast kinetics (2–40 times faster than the state-of-the-art catalysts) and ultra-high mineralization (82.3% within 80 min) for TCL degradation; (2) Cu2O/MIL(Fe/Cu) showed a promising cycling stability due to improved charge transfer ability that could protect Cu2O from photo-corrosion during photo-Fenton reaction; (3) The catalytic performance of Cu2O/MIL(Fe/Cu) was characterized and seven photocatalytic intermediates were identified by both HPLC/MS and Surface Enhanced Raman Spectroscopy. The cyanoimino group in TCL was proved for the first time to be attacked primarily. Moreover, among all the detected intermediates, thiazolidin-2-amine (P6) was found to be the most stable intermediate to be degraded, and it can directly influence the TOC determination during photodegradation process.