摘要
The adsorbents–adsorbates interaction is critical for resourcelization in heavy metal wastewater treatment.Nevertheless,it is still indistinct to depict the impact of metal center effect on heavy metals removal performance in metal-organic frameworks(MOFs)-based adsorbents.Herein,a series of MOFs with different metal centers of Mg(II),La(III),and Zr(IV)are rationally designed,and the effect of electronic structure on the Sb(V)removal performance is systematically investigated.The obtained La-MGs achieve Sb(V)adsorption capacity of 897.6 mg/g,which is about 1.2 and 4.5 times above average than those of Zr-MGs and Mg-MGs,respectively.On account of more edge adsorption sites achieve,the sites utilization efficiency of La-MGs(92.1%)is much better than Zr-MGs(75.0%)and Mg-MGs(20.4%).Furthermore,density functional theory(DFT)calculations reveal that La-MGs are more active than Mg-MGs and Zr-MGs,owing to the lower adsorption energy,higher charge transfer,and stronger bonding interaction,which will promote the Sb(V)removal performance.The experimental results in practical water indicate that La-MGs effectively capture antimony at low concentration,reaching drinking water standard in samples from Ganjiang River.This study opens an avenue for atomic-level insight into high-efficient absorbents design for water treatment from electronic structuremodification of active centers.
基金
the National Natural Science Foundation of China(Nos.51938007,51720105001,52100039,52125002,and 52100043)
the Youth Natural Science Foundation of Hunan Province(No.2020JJ5076).