Fabrication ofγ-Fe2O3Nanoparticles by Solid-State Thermolysis of a Metal-Organic Framework, MIL-100(Fe), for Heavy Metal Ions Removal

Shengtao Hei,Yan Jin,Fumin Zhang

doi:10.1155/2014/546956

Abstract

Porousγ-Fe2O3nanoparticles were prepared via a solid-state conversion process of a mesoporous iron(III) carboxylate crystal, MIL-100(Fe). First, the MIL-100(Fe) crystal that served as the template of the metal oxide was synthesized by a low-temperature (<100°C) synthesis route. Subsequently, the porousγ-Fe2O3nanoparticles were fabricated by facile thermolysis of the MIL-100(Fe) powders via a two-step calcination treatment. The obtainedγ-Fe2O3was characterized by X-ray diffraction (XRD), N2adsorption, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) techniques, and then used as an adsorbent for heavy metal ions removal in water treatment. This study illustrates that the metal-organic frameworks may be suitable precursors for the fabrication of metal oxides nanomaterials with large specific surface area, and the prepared porousγ-Fe2O3exhibits a superior adsorption performance for As(V) and As(III) ions removal in water treatment.

Highlights

As(V) and As(III) are considered as primarily highly toxic pollutants in water resources due to their wide spread use in industrial processes, and their efficient removal from water is of great importance
Metal-organic frameworks (MOFs) with diverse architectures and morphologies have been recognized as promising precursors/templates to develop the porous iron oxides [25,26,27,28,29,30,31,32]
Xu and coworkers reported the fabrication of spindle-like mesoporous α-Fe2O3 using metal-organic frameworks (MOFs) MIL-88(Fe) as template [25]

Summary

Introduction

As(V) and As(III) are considered as primarily highly toxic pollutants in water resources due to their wide spread use in industrial processes, and their efficient removal from water is of great importance. Fabrication of the porous γ-Fe2O3 nanoparticles with a high specific surface area that favors a high adsorption capacity, as well as the separation of the saturated adsorbents so as to prevent secondary pollution during their usage, is still a challenging topic. MIL-100(Fe), a novel mesoporous MOF, has a large BET specific surface area and pore volume with the presence of a significant amount of accessible Lewis acid metal sites upon dehydration [33, 34].

Results

Conclusion