Lattice-Defect-Enhanced Adsorption of Arsenic on Zirconia Nanospheres: A Combined Experimental and Theoretical Study

Abstract

Zirconium oxide (ZrO2) nanoadsorbents exhibit great potential in the remediation of arsenic-polluted water. However, physicochemical structure–adsorption performance relationship is not well-understood, which retards further development of high-performance ZrO2 nanoadsorbents. Herein, a facile-controlled crystallization strategy was developed to synthesize defective ZrO2 with the assistance of organic ligands. Systematic characterizations showed that this proposed synthesis strategy can be exploited to regulate the defective density of ZrO2, whereas other structural properties remain almost unchanged. Batch adsorption experiments exhibited that UiO-66-SH-A with a higher lattice defect possessed a larger capacity and a faster rate for the uptake of As­(III)/As­(V). The maximum capacities of UiO-66-SH-A to uptake As­(III) and As­(V) were up to 90.7 and 98.8 mg/g, respectively, which are 12.3 and 11.5 times larger than those of UiO-66-A. These results from the structure–performance analysis and theoretical calculations further reveal that lattice defect plays a key role in the enhancement of arsenic adsorption on ZrO2. We hope this new understanding of the structure-dependent adsorption performance will provide a valuable insight for designing Zr-based nanoadsorbents to capture arsenic.

Facile fabrication of bimetallic Fe–Mg MOF for the synthesis of xanthenes and removal of heavy metal ions

“…A value of 1/n lower than unity is indicative of Langmuir isotherm while 1/n above unity indicating of co-operative sorption. 68 Langmuir and Freundlich sorption isotherms for Pb(II), Cd(II) and Cu(II) using (0.6 : 1) Fe-Mg MOF as adsorbent are seen in Fig. S4.…”

Metal Organic Frameworks to Remove Arsenic Adsorption from Wastewater

“…Adsorption energies and geometry calculations too were performed using density functional theory studies. Shao P et al reported enhanced adsorption of zirconia using theoretical study and quantum calculation leading to a profound understanding of the structural features and adsorption of As(III) or As(V) [92]. The defect densities of the synthesized ZrO 2 were analyzed using density functional theory calculations.…”

Effective and selective removal of phosphate from water by the Co(II)-based adsorbent

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