Synthesis and evaluation of the SERS effect of Fe(3)O(4)–Ag Janus composite materials for separable, highly sensitive substrates

Fe(3)O(4)–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 10(9) compared with the values of other Fe(3)O(4)–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 Fe(3)O(4)–Ag Janus composite particles have promise for application as separable, highly sensitive SERS substrates.