“…A surface plasmon is a collective oscillation of free electrons excited by photons on the metal, which generates a huge enhanced electromagnetic field on the metal surface. This strongly enhanced electromagnetic field can be applied to the field of nano-optics, such as surface enhanced spectroscopy, − ultrasensors, , water splitting, , light traps, ultra-diffraction-limited optical waveguides, and so forth. In recent years, an interesting surface-enhanced Raman scattering (SERS)-related phenomenon called plasmon-driven surface catalysis (PDSC) has been reported by many groups, in which p -aminothiophenol (PATP) or 4-nitrobenzenethiol (4-NBT) could be converted into p , p ′-dimercaptoazobenzene (DMAB) molecules with the help of surface plasmons near the metal surface. − In this phenomenon, the Raman peaks at 1143, 1390, and 1432 cm –1 are derived from newly generated DMAB molecules instead of the original PATP or 4-NBT molecules.…”