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Direct Synthesis of Novel and Reactive Sulfide-modified Nano Iron through Nanoparticle Seeding for Improved Cadmium-Contaminated Water Treatment.

Su Y, Adeleye AS, Huang Y, Zhou X, Keller AA, Zhang Y - Sci Rep (2016)

Bottom Line: Syntheses monitoring experiments show that seeding accelerates the reduction rate from Fe(2+) to Fe(0) by 19%.Both X-ray diffraction and Mössbauer analyses further confirm that increased nanoparticle seeding results in formation of more Fe(0) crystals.The synthesized nanohybrid has high cadmium removal capacity and holds promising prospects for treatment of metal-contaminated water.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China.

ABSTRACT
Magnetic sulfide-modified nanoscale zerovalent iron (S-nZVI) is of great technical and scientific interest because of its promising application in groundwater remediation, although its synthesis is still a challenge. We develop a new nanoparticle seeding method to obtain a novel and reactive nanohybrid, which contains an Fe(0) core covered by a highly sulfidized layer under high extent of sulfidation. Syntheses monitoring experiments show that seeding accelerates the reduction rate from Fe(2+) to Fe(0) by 19%. X-ray adsorption near edge structure (XANES) spectroscopy and extended X-ray absorption fine structure analyses demonstrate the hexahedral Fe-Fe bond (2.45 and 2.83 Å) formation through breaking down of the 1.99 Å Fe-O bond both in crystalline and amorphous iron oxide. The XANES analysis also shows 24.2% (wt%) of FeS with bond length of 2.4 Å in final nanohybrid. Both X-ray diffraction and Mössbauer analyses further confirm that increased nanoparticle seeding results in formation of more Fe(0) crystals. Nano-SiO2 seeding brings down the size of single Fe(0) grain from 32.4 nm to 18.7 nm, enhances final Fe(0) content from 5.9% to 55.6%, and increases magnetization from 4.7 to 65.5 emu/g. The synthesized nanohybrid has high cadmium removal capacity and holds promising prospects for treatment of metal-contaminated water.

No MeSH data available.


Related in: MedlinePlus

XRD patterns of nZVI, S-nZVI synthesized in plastic and glass beaker, and S-nZVI synthesized with different dosage of seeding nanoparticles.(◼, peaks for Fe0; , peaks for NaCl).
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f4: XRD patterns of nZVI, S-nZVI synthesized in plastic and glass beaker, and S-nZVI synthesized with different dosage of seeding nanoparticles.(◼, peaks for Fe0; , peaks for NaCl).

Mentions: Some NaCl was observed in all S-nZVI and FeSSi particles (Fig. 4). Na+ was contributed by sodium dithionite and sodium borohydride, while the Cl− ions came from the ferric chloride. Sodium and chloride were adsorbed onto the iron cluster, providing the electrostatic repulsion. This explains the well-dispersion of S-nZVI and FeSSi observed during the syntheses.


Direct Synthesis of Novel and Reactive Sulfide-modified Nano Iron through Nanoparticle Seeding for Improved Cadmium-Contaminated Water Treatment.

Su Y, Adeleye AS, Huang Y, Zhou X, Keller AA, Zhang Y - Sci Rep (2016)

XRD patterns of nZVI, S-nZVI synthesized in plastic and glass beaker, and S-nZVI synthesized with different dosage of seeding nanoparticles.(◼, peaks for Fe0; , peaks for NaCl).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4837343&req=5

f4: XRD patterns of nZVI, S-nZVI synthesized in plastic and glass beaker, and S-nZVI synthesized with different dosage of seeding nanoparticles.(◼, peaks for Fe0; , peaks for NaCl).
Mentions: Some NaCl was observed in all S-nZVI and FeSSi particles (Fig. 4). Na+ was contributed by sodium dithionite and sodium borohydride, while the Cl− ions came from the ferric chloride. Sodium and chloride were adsorbed onto the iron cluster, providing the electrostatic repulsion. This explains the well-dispersion of S-nZVI and FeSSi observed during the syntheses.

Bottom Line: Syntheses monitoring experiments show that seeding accelerates the reduction rate from Fe(2+) to Fe(0) by 19%.Both X-ray diffraction and Mössbauer analyses further confirm that increased nanoparticle seeding results in formation of more Fe(0) crystals.The synthesized nanohybrid has high cadmium removal capacity and holds promising prospects for treatment of metal-contaminated water.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China.

ABSTRACT
Magnetic sulfide-modified nanoscale zerovalent iron (S-nZVI) is of great technical and scientific interest because of its promising application in groundwater remediation, although its synthesis is still a challenge. We develop a new nanoparticle seeding method to obtain a novel and reactive nanohybrid, which contains an Fe(0) core covered by a highly sulfidized layer under high extent of sulfidation. Syntheses monitoring experiments show that seeding accelerates the reduction rate from Fe(2+) to Fe(0) by 19%. X-ray adsorption near edge structure (XANES) spectroscopy and extended X-ray absorption fine structure analyses demonstrate the hexahedral Fe-Fe bond (2.45 and 2.83 Å) formation through breaking down of the 1.99 Å Fe-O bond both in crystalline and amorphous iron oxide. The XANES analysis also shows 24.2% (wt%) of FeS with bond length of 2.4 Å in final nanohybrid. Both X-ray diffraction and Mössbauer analyses further confirm that increased nanoparticle seeding results in formation of more Fe(0) crystals. Nano-SiO2 seeding brings down the size of single Fe(0) grain from 32.4 nm to 18.7 nm, enhances final Fe(0) content from 5.9% to 55.6%, and increases magnetization from 4.7 to 65.5 emu/g. The synthesized nanohybrid has high cadmium removal capacity and holds promising prospects for treatment of metal-contaminated water.

No MeSH data available.


Related in: MedlinePlus