PEI grafted defective MOF-808 for enhanced boron removal

Herein, we presented a facile method for enhanced boron removal based on PEI-grafted defective MOF-808 (D-MOF-808/PEI). The rich Zr–OH bonds, amino-functionalized surface, and exposed metal defects of D-MOF-808/PEI endow it with the high adsorption capacity of boron. Due to the ligand exchange at metal defects and boron-imine/amine groups complexation, D-MOF-808/PEI exhibits exceptional selectivity for boron with the saturation adsorption of 95.30 mmol·g⁻¹ at 45 °C. Additionally, negligible interference from other coexistent ions and excellent reusability promote the application of D-MOF-808/PEI practically for the rapid and high selectivity removal of boron from complex environmental samples. This work furnishes a promising strategy for boron contamination and expands the application potential of defective MOF-based adsorbents for environmental remediation.