Iron Oxide–Gold Composite
Nanoparticles and Nano-Gap Junctions
for Sensing Applications Using
Surface-Enhanced Raman Scattering
Simona E. Hunyadi Murph and Emily Searles
Abstract Multifunctional iron oxide–gold composite nanostructures with tailored
“hot-spot” nano-gap junctions have been produced via a multi-seed-mediated
approach and investigated for analyte detection. Tunable nano-gap “hotspot” junctions based on gold nanospheres were rationally created on iron oxide surface and
evaluated for surface-enhanced Raman scattering (SERS) enhancement studies for
a model reporter analyte, 4-mercaptophenol. Surface-enhanced Raman scattering
studies show a three-time enhancement effect for composite gold–iron oxide nanoparticles when compared with gold nanostructures. These enhancements are attributed to
the presence of the “hot-spot” junctions and nano-gaps obtained from both: (a) multiseed-mediated approach that generates larger decoration of iron oxide with plasmonic
nanoparticles and (b) aggregated assemblies formed due to the key magnetic iron
oxide nanostructures.
Keywords Composite nanostructures · Gold–iron oxide nanomaterials · Sensing ·
Surface-enhanced raman scattering
Introduction
Incident light scatters as it transmits through chemical species. The extent to which
the electric field is distorted and the degree to which the light is scattered is a measure
of the polarizability of the species of interest [1]. By analyzing the extent to which
the species scatters light, a unique fingerprint of the species can be observed. This
fingerprint is derived from the distinctive inelastic collision scattering signal, known
S. E. H. Murph (B) · E. Searles
Savannah River National Laboratory, Environmental and Biotechnology Directorate, Aiken, SC,
USA
e-mail: Simona.Murph@srnl.doe.gov
S. E. H. Murph
Department of Physics and Astronomy, University of Georgia, Athens, GA, USA
© The Minerals, Metals & Materials Society 2021
T. S. Srivatsan et al. (eds.), Metal-Matrix Composites, The Minerals, Metals
& Materials Series, https://doi.org/10.1007/978-3-030-65249-4_17
255
Nanoparticles and Nano-Gap Junctions
for Sensing Applications Using
Surface-Enhanced Raman Scattering
Simona E. Hunyadi Murph and Emily Searles
Abstract Multifunctional iron oxide–gold composite nanostructures with tailored
“hot-spot” nano-gap junctions have been produced via a multi-seed-mediated
approach and investigated for analyte detection. Tunable nano-gap “hotspot” junctions based on gold nanospheres were rationally created on iron oxide surface and
evaluated for surface-enhanced Raman scattering (SERS) enhancement studies for
a model reporter analyte, 4-mercaptophenol. Surface-enhanced Raman scattering
studies show a three-time enhancement effect for composite gold–iron oxide nanoparticles when compared with gold nanostructures. These enhancements are attributed to
the presence of the “hot-spot” junctions and nano-gaps obtained from both: (a) multiseed-mediated approach that generates larger decoration of iron oxide with plasmonic
nanoparticles and (b) aggregated assemblies formed due to the key magnetic iron
oxide nanostructures.
Keywords Composite nanostructures · Gold–iron oxide nanomaterials · Sensing ·
Surface-enhanced raman scattering
Introduction
Incident light scatters as it transmits through chemical species. The extent to which
the electric field is distorted and the degree to which the light is scattered is a measure
of the polarizability of the species of interest [1]. By analyzing the extent to which
the species scatters light, a unique fingerprint of the species can be observed. This
fingerprint is derived from the distinctive inelastic collision scattering signal, known
S. E. H. Murph (B) · E. Searles
Savannah River National Laboratory, Environmental and Biotechnology Directorate, Aiken, SC,
USA
e-mail: Simona.Murph@srnl.doe.gov
S. E. H. Murph
Department of Physics and Astronomy, University of Georgia, Athens, GA, USA
© The Minerals, Metals & Materials Society 2021
T. S. Srivatsan et al. (eds.), Metal-Matrix Composites, The Minerals, Metals
& Materials Series, https://doi.org/10.1007/978-3-030-65249-4_17
255