Tunable rare-earth metal-organic frameworks for ultra-high selenite capture

Linkers and clusters with various conformations present challenges for the design and prediction of highly porous and stable rare-earth metal-organic frameworks (RE-MOFs) for trapping toxic ions in aqueous solutions. Herein, we designed and synthesized a series of RE-MOFs based on a malleable ligand to explore the effects of ligands, clusters, and configurations on structural stability. The results showed that the nonanuclear high-connected UPC183 exhibited better stability than the hexanuclear low-connected RE-MOF (UPC-181/182 series). Due to the syngenetic effect of chemi- and physisorption, the adsorption capacity of UPC-183-Eu for selenite (SeO32-) is as high as 308.39 mg/g, recorded one of the highest ever reported for MOFs. Furthermore, we accurately analyzed the adsorption site of UPC-183-Eu for SeO32- through single-crystal structure and theoretical simulation. The ultra-high selenite adsorption capacity and removal efficiency endow UPC-183-Eu an excellent porous adsorbent for removing pollutants.

Automated summary

In this study, a series of rare-earth metal-organic frameworks (RE-MOFs) were designed and synthesized to investigate the effects of ligands, clusters, and configurations on the structural stability and adsorption performance. The results showed that UPC183 exhibited better stability than the UPC-181/182 series, and UPC-183-Eu showed an ultra-high adsorption capacity for selenite, one of the highest reported for MOFs. The accurate analysis of the adsorption site using single-crystal structure and theoretical simulation further supported the excellent performance of UPC-183-Eu as a porous adsorbent for pollutant removal.