Metal-organic frameworks as superior adsorbents for pesticide removal from water: The cutting-edge in characterization, tailoring, and application potentials

Pesticides are top-priority contaminants, and the highly efficient removal of pesticides from wastewater is of vital importance due to their significant risk to the ecological environment and human health. Metal-organic frameworks (MOFs) have a large specific surface area, adjustable aperture size, easy modification and facile production, which have been demonstrated to be a superior platform for pesticide adsorption. This review highlights the advances in reported MOF-based materials as robust candidates for efficient pesticide capture from water. The adsorption performance and related mechanisms of MOF-based adsorbents for different types of pesticides were evaluated and compared with those of traditional adsorbents. Macroscopic batch techniques, microscopic spectral analysis and theoretical calculations are efficient for analyzing the pesticide adsorption behaviors and mechanisms by MOF. Complex host–guest interactions including coordination, electrostatic interactions, hydrogen bonding, π-π interactions/stacking, acid-base interactions and hydrophobic interactions participate in the pesticide adsorption process. Strategies including enlarging pores, introducing functionalities, charging surfaces and hydrophobicity can efficiently promote the pesticide adsorption efficiency. With continuous research, more MOF-based adsorbents with low cost, large-scale production, outstanding stability, easy separation and excellent reusability have been developed, which promotes the practical application of MOF-based materials. Finally, possible research challenges and perspectives in this field are proposed to stimulate more possibilities for future work.