Facile Hydrothermal Synthesis of Nanostructured Hollow Iron–Cerium Alkoxides and Their Superior Arsenic Adsorption Performance

Abstract

Recently, metal oxides with novel nanostructured architectures have been prepared by annealing the polyol-based metal alkoxides for water treatment. However, these materials often exhibit relatively low adsorption capacities possibly attributable to the decomposition of surface groups during the calcination process. In this work, we successfully synthesized a novel nanostructured hollow iron-cerium alkoxide (NH-ICA) with a high surface area and abundant surface functional groups through an ethylene glycol mediated solvothermal method. Cerium ion doping significantly influenced the morphologies, microstructures and adsorption performance of NH-ICAs. Interestingly, the synthesized NH-ICAs showed significantly higher affinity to As(III) than the iron alkoxide material without cerium doping. Moreover, a much higher adsorption capacity of the NH-ICAs for As(III) than As(V) was found. When the molar ratio of Fe to Ce was 5:1, the product with uniform nanostructured hollow architectures exhibited the best adsorption capacities for both As(V) and As(III) (206.6 and 266.0 mg g(-1), respectively). The mechanistic study revealed that As(V) adsorption involved ion-exchange between the As(V) species and three types of negatively charged groups, including surface hydroxyl groups, CO3(2-) and unidentate carbonate-like species. For As(III) adsorption, surface complexing was proposed. A broad adaptation pH range for both As(V) and As(III) adsorbed by the resulting product indicates its promising application perspective for decontamination of arsenic-polluted water.

CoFe2O4@MIL-100(Fe) hybrid magnetic nanoparticles exhibit fast and selective adsorption of arsenic with high adsorption capacity

“…Thus, chemisorption occurred during the iAs removal process. Valence forces through the sharing or exchange of electrons were involved between iAs and the hybrid MNPs, which agreed well with previous reports about the formation of the Fe-O-As structure3953.…”

Arsenic Adsorption on Lanthanum-Impregnated Activated Alumina: Spectroscopic and DFT Study

“…The 6-311+G (d, p) basis set for As, H, and O 22,23 was used with a scale factor of 0.967, 24 and the LanL2DZ basis set was employed for La 25−27 with a scale factor of 0.961. 24 An edge-sharing seven-coordinated hexagonal cluster 28,29 was used to simulate neutral La 2 (OH) 6 (OH 2 ) 6 ·4(H 2 O) and positively charged La 2 (OH) 5 (OH 2 ) 7 · 4(H 2 O) surfaces. The solvation effect was considered by using an implicit continuum model (IEFPCM) combined with 8 H 2 O molecules around As(V) and As(III) and 4 H 2 O molecules around surface complexes.…”

Simultaneous removal of arsenate and antimonate in simulated and practical water samples by adsorption onto Zn/Fe layered double hydroxide

“…Based on our previous researches on arsenic adsorption with several novel materials [27][28][29], the objective of this work is to develop an efficient functional material for the adsorption of coexistent As(V) and Sb(V) in water, and investigate the possibility of simultaneous removal of both arsenate and antimonate for practical polluted water samples. In this study, a ferric-based layered double hydroxide material (Zn-Fe-LDH) has been synthesized and used to study the adsorption performance for arsenate and antimonate in aqueous solutions.…”