Synthesis of a novel microplastic trap with abundant oxime groups based on MOF-545 post-engineering for the environmental pollution control and water remediation

Abstract

The elimination of microplastics (MPs) from aquatic systems is a great challenge because of its miniature dimension and exorbitant stability. Hence, a novel MP trap with abundant oxime groups (MOF-545-oxime) was triumphantly synthesized based on MOF-545 post-engineering. The supreme MP adsorption capacity of MOF-545-oxime was 294.6 mg/g, which also manifested excellent selectivity and reusability for MP adsorption. Moreover, the kinetic, isothermal and thermodynamic models were used to inquiry the MP adsorption mechanism, which was governed by electrostatic attraction, coordination, and π–π interactions. The XPS spectra and adsorption energy calculations upheld the CN–OH and CN groups executed a pivotal part in the MP adsorption process of MOF-545-oxime. MOF-545-oxime also possessed splendid anti-biofouling activity and environmental safety, which efficaciously diminished the pessimistic influences of Halamphora upon the MP adsorption capacity and complied with the requirements for non-toxicity and innocuousness in the adsorbent application. The superb anti-biofouling activity and environmental safety of MOF-545-oxime might be due to the abundant functional groups and stable chemical structure. Indubitably, the development of efficacious adsorbents is crucial for the MP removal from aquatic systems. The originally proposed MOF-545-oxime has a great potential to remove MPs from aquatic systems, which also offers an inspiration for perfect high-efficiency adsorbents.