Surface-enhanced Raman spectroscopy (SERS) is a powerful technique that provides fingerprint vibrational information with ultrahigh sensitivity, even down to single molecular level. However, only a few metals (gold, silver, and copper) yield a large SERS effect, and they must be rough at the nanoscale (material and morphology limitation). Shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) was therefore invented to break the long-standing limitation of SERS. In SHINERS, Au/Ag@SiO2core-shell nanoparticles are used as “smart dust” to enhance the Raman signals of molecules nearby. The Au/Ag core works as the Raman amplifier to enhance the Raman signals of probed molecules, while the ultra-thin, uniform and pinhole-free silica shell prevents the Au/Ag core from interacting with analytical targets or the chemical environment, thus, providing the original information from the target systems. Due to the extraordinary advantages of SHINERS, it has already been widely applied in various fields including electrochemistry, bioscience, material science, and even people’s daily life.
Our group also focuses on the design and synthesis of a variety of plasmonic nanomaterials with core-shell structures that possess ultrahigh SERS activities. Au-core transition metal-shell nanoparticles (Au@TM, where TM = Pt, Pd, Rh, Ru, etc.) and Au/Ag-core dielectric-shell nanoparticles (Au@DE, where DE = SiO2, TiO2, Al2O3, MnO2, graphene, MOF, CdS, etc.) were rationally synthesized for SERS, SHINERS, fluorescence, and other plasmon-enhanced spectroscopy. Such core-shell nanomaterials have also been used in the energy-related applications including photocatalysis, solar cells, and other electrochemical devices. We have also designed core-shell nanotips for SECM, STM, tip-enhanced Raman and fluorescence spectroscopy.
