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S. E. H. Murph and A. Goriounova
confirmed the presence of zinc (Fig. 10). It is worth mentioning that the filters
were washed in deionized water prior analysis. The untreated stainless-steel wool
filters did not capture any zinc. While energy-dispersive X-Ray spectroscopy is
a semi-quantitative study, the preliminary compositional data analysis suggests a
5:1 ratio of gold:zinc. The presence of zinc shows that L-cysteine-capped gold
nanoparticle-treated stainless-steel wool filters are effective at the uptake of heavy
metals.
The results at this study, while crude, could offer the foundation for the development of efficient filters and membranes [25] that could aid the conventional filtration systems based on membrane filtration, reverse osmosis, ion exchange, chemical precipitation, electrodialysis, electrochemical treatment, and adsorption. Further
studies are underway and will be reported later.
Conclusions
We developed a nanomaterial-treated filter for the uptake of heavy metals from
contaminated water sources. The research manuscript’s highlights include:
• We demonstrate the successful synthesis and characterization of gold nanoparticles in solution and on stainless-steel wool filters.
• We developed two different sequestration technologies for heavy metals based
on the surface functionalization of gold nanoparticles with two different ligands:
citrate and L-cysteine.
• Citrate-capped gold nanoparticles can be efficiently used as a colorimetric sensor
in solution.
• Citrate-capped gold nanoparticles show a greater heavy metal loading capacity
than L-cysteine-functionalized gold nanoparticles. The citrate-capped gold
nanoparticles have a greater sensitivity for copper (II) than zinc (II).
• L-cysteine-capped gold nanoparticles are more sensitive toward incremental
uptake of zinc (II) ions making them valuable for sensing and sequestration
applications.
• L-cysteine-capped gold nanoparticlestainless-steel wool filters are efficient at the
uptake of heavy metal ions and could be used for environmental remediation
applications.
Acknowledgements We would like to thank the Science Undergraduate Laboratory Internship
(SULI) operated by the DOE-Office of Science and the Savannah River National Laboratory financial support. This work was supported by the Laboratory Directed Research and Development
(LDRD) program (LDRD-2015-00040) within the Savannah River National Laboratory (SRNL).
This document was prepared in conjunction with work accomplished under Contract No. DE-AC0908SR22470 with the U.S. Department of Energy (DOE) Office of Environmental Management
(EM).
S. E. H. Murph and A. Goriounova
confirmed the presence of zinc (Fig. 10). It is worth mentioning that the filters
were washed in deionized water prior analysis. The untreated stainless-steel wool
filters did not capture any zinc. While energy-dispersive X-Ray spectroscopy is
a semi-quantitative study, the preliminary compositional data analysis suggests a
5:1 ratio of gold:zinc. The presence of zinc shows that L-cysteine-capped gold
nanoparticle-treated stainless-steel wool filters are effective at the uptake of heavy
metals.
The results at this study, while crude, could offer the foundation for the development of efficient filters and membranes [25] that could aid the conventional filtration systems based on membrane filtration, reverse osmosis, ion exchange, chemical precipitation, electrodialysis, electrochemical treatment, and adsorption. Further
studies are underway and will be reported later.
Conclusions
We developed a nanomaterial-treated filter for the uptake of heavy metals from
contaminated water sources. The research manuscript’s highlights include:
• We demonstrate the successful synthesis and characterization of gold nanoparticles in solution and on stainless-steel wool filters.
• We developed two different sequestration technologies for heavy metals based
on the surface functionalization of gold nanoparticles with two different ligands:
citrate and L-cysteine.
• Citrate-capped gold nanoparticles can be efficiently used as a colorimetric sensor
in solution.
• Citrate-capped gold nanoparticles show a greater heavy metal loading capacity
than L-cysteine-functionalized gold nanoparticles. The citrate-capped gold
nanoparticles have a greater sensitivity for copper (II) than zinc (II).
• L-cysteine-capped gold nanoparticles are more sensitive toward incremental
uptake of zinc (II) ions making them valuable for sensing and sequestration
applications.
• L-cysteine-capped gold nanoparticlestainless-steel wool filters are efficient at the
uptake of heavy metal ions and could be used for environmental remediation
applications.
Acknowledgements We would like to thank the Science Undergraduate Laboratory Internship
(SULI) operated by the DOE-Office of Science and the Savannah River National Laboratory financial support. This work was supported by the Laboratory Directed Research and Development
(LDRD) program (LDRD-2015-00040) within the Savannah River National Laboratory (SRNL).
This document was prepared in conjunction with work accomplished under Contract No. DE-AC0908SR22470 with the U.S. Department of Energy (DOE) Office of Environmental Management
(EM).