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Synthesis and evaluation of the SERS effect of Fe₃O₄-Ag Janus composite materials for separable, highly sensitive substrates.

ABSTRACT: Fe₃O₄-Ag Janus composites were synthesized using a two-step solvothermal method. The optimal growth process was determined by investigating the relationship between the particle morphologies and reaction time. Magnetic and Raman spectroscopic measurements showed that the as-synthesized Janus composites have both good magnetic response and significant surface-enhanced Raman scattering (SERS) effects, as well as reproducibility. The calculated Raman enhancement factor reached an unprecedented magnitude of 10⁹ compared with the values of other Fe₃O₄-Ag compounds. Furthermore, the SERS effect was exhibited even at a concentration of probe molecules as low as 10^-13 M. This demonstrates that the as-synthesized Fe₃O₄-Ag Janus composite particles have promise for application as separable, highly sensitive SERS substrates.

SUBMITTER: Li Y

PROVIDER: S-EPMC9059953 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Synthesis and evaluation of the SERS effect of Fe3O4-Ag Janus composite materials for separable, highly sensitive substrates.

Li Yanlin Y Yang Sen S Lu Xuegang X Duan Wenyuan W Moriga Toshihiro T

RSC advances 20190122 6

Fe3O4-Ag Janus composites were synthesized using a two-step solvothermal method. The optimal growth process was determined by investigating the relationship between the particle morphologies and reaction time. Magnetic and Raman spectroscopic measurements showed that the as-synthesized Janus composites have both good magnetic response and significant surface-enhanced Raman scattering (SERS) effects, as well as reproducibility. The calculated Raman enhancement factor reached ...[more]

PMID: 35518983

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