Surface chemistry and electrochemistry of supported zerovalent iron nanoparticles in the remediation of aqueous metal contaminants

S. M. Ponder, J. G. Darab, J. Bucher, D. Caulder, I. Craig, L. Davis, N. Edelstein, W. Lukens, H. Nitsche, L. Rao, D. K. Shuh, T. E. Mallouk

Research output: Contribution to journalArticle

226 Scopus citations

Abstract

The microstructure, physical characteristics, corrosion behavior, and reactivity of zerovalent iron nanoparticles synthesized on a support (primarily a nonporous, hydrophobic polymer resin) were studied. The remediation of groundwater by zerovalent iron in in situ permeable reactive barriers relies on the redox reaction between metallic iron and a reducible contaminant. Decreasing the size of the iron particles and dispersing them on a support increases the specific surface area of the iron, as well as the ratio of surface to bulk iron atoms, and should thereby increase both the reaction rate and the fraction of iron atoms available for the reaction. Borohydride reduction of aqueous ferrous sulfate gives supported iron nanoparticles, 10-30 nm in diameter, which consist of 85% zerovalent iron by weight. These materials ("ferragels") are stable in air and have corrosion behavior comparable to iron filings. Interestingly, the presence or absence of a support, as well as the boron remaining from the borohydride reduction process, influences the electrochemical corrosion rate of the composite materials. Supported and unsupported zerovalent iron nanoparticles are superior to iron filings in both terms of initial rates of reduction and total moles of contaminants (Cr(VI), Pb(II), TcO4-) reduced per mole of iron. The enhanced reactivity and passive corrosion behavior of these materials should make them good candidates for use in permeable reactive barriers.

Original languageEnglish (US)
Pages (from-to)479-486
Number of pages8
JournalChemistry of Materials
Volume13
Issue number2
DOIs
StatePublished - Mar 19 2001

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Chemical Engineering(all)
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Surface chemistry and electrochemistry of supported zerovalent iron nanoparticles in the remediation of aqueous metal contaminants'. Together they form a unique fingerprint.

  • Cite this

    Ponder, S. M., Darab, J. G., Bucher, J., Caulder, D., Craig, I., Davis, L., Edelstein, N., Lukens, W., Nitsche, H., Rao, L., Shuh, D. K., & Mallouk, T. E. (2001). Surface chemistry and electrochemistry of supported zerovalent iron nanoparticles in the remediation of aqueous metal contaminants. Chemistry of Materials, 13(2), 479-486. https://doi.org/10.1021/cm000288r