Yan,W., Herzing,A.A., Kiely,C.J. and Zhang,W.-x.(2010): Nanoscale zero-valent iron (nZVI): Aspects of the core-shell structure and reactions with inorganic species in water. Journal of Contaminant Hydrology, 118, 96-104.

『ナノスケールの電荷０の鉄（nZVI）：水中の無機化学種に伴う核−殻構造と反応の様相』

『Abstract
　Aspects of the core-shell model of nanoscale zero-valent iron (nZVI) and their environmental implications were examined in this work. The structure and elemental distribution of nZVI were characterized by X-ray energy-dispersive spectroscopy (XEDS) with nanometer-scale spatial resolution in an aberration-corrected scanning transmission electron microscope (STEM). The analysis provides unequivocal evidence of a layered structure of nZVI consisting of a metallic iron core encapsulated by a thin amorphous oxide shell. Three aqueous environmental contaminants, namely Hg(II), Zn(II) and hydrogen sulfide, were studied to probe the reactive properties and the surface chemistry of nZVI. High-resolution X-ray photoelectron spectroscopy (HR-XPS) analysis of the reacted particles indicated that Hg(II) was sequestrated via chemical reduction to elemental mercury. On the other hand, Zn(II) removal was achieved via sorption to the iron oxide shell followed by zinc hydroxide precipitation. Hydrogen sulfide was immobilized on the nZVI surface as disulfide (S2-3) and monosulfide (S2-) species. Their relative abundance in the final products suggests that the retention of hydrogen sulfide occurs via reactions with the oxide shell to form iron sulfide (FeS) and subsequent conversion to iron disulfide (FeS2). The results presented herein highlight the multiple reactive pathways permissible with nZVI owing to its two functional constituents. The core-shell structure imparts nZVI with manifold functional properties previously unexamined and grains the material with potentially new applications.

Keywords: Zero-valent iron; Nanoparticles; Core-shell model; Hydrogen sulfide; Heavy metals; Mercury; Zinc』

1. Introduction
2. Methods and materials
　2.1. Synthesis of iron nanoparticles
　2.2. Electron microscopy characterization
　2.3. X-ray photoelectron spectroscopy
　2.4. Batch experiments
　2.5. Analytical methods
3. Results and discussion
　3.1. Characterizing the nanostructure of nZVI
　3.2. Reduction property of nZVI - removal of Hg(II)
　3.3. Sorption and precipitation - removal of Zn(II)
　3.4. Sorption and surface mineralization - sequestration of H2S
4. Conclusion
Acknowledgements
References

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