Water-Stable Amino-Functionalized Coordination Polymer for Efficient Hg2+ Capture

Hg2+ pollution seriously harms human life and health, and it is of great significance to develop Hg2+ removal materials with excellent performance. In this work, a crystalline coordination polymer material {[Zn(L)(A)]·DMF}n (1) with 4.8 mmol/g amino loading density was engineered by using amino-functionalized ligands. Strong coordination properties of isonicotinic acid and adenine endow 1 with excellent chemical stability and thermal stability. Results of the removal experiment showed that 1 could efficiently remove >96% Hg2+ within 10 min, and the saturated adsorption amount was 273 mg/g, which shows advantages over most reported MOF adsorbents. After combining IR spectra, XPS spectra, and CO2 adsorption results, displacement of the characteristic peak demonstrated that the excellent capture performance is mainly attributed to the coordination interaction between high-density amino groups and Hg2+. This work provides a new consideration for the practical application of MOF adsorbents.