Selective Plasmon Driven Surface Catalysis in Metal Triangular Nanoplate-Molecule-Film Sandwich Structure

Combined with surface enhanced Raman scattering (SERS) and finite difference time-domain (FDTD) method, the plasmon-driven surface catalytic (PDSC) reaction of p,p′-dimercaptoazobenzene (DMAB) produced from 4-nitrobenzenethiol (4NBT) or P-aminothiophenol (PATP) in Au triangular nanoplate-molecule-film sandwich structure is investigated. The disparity of SERS spectra at different positions on Au triangular nanoplate indicates that the surface catalysis is selective performed at some particular regions, which change along with the polarization direction of the incident laser. Furthermore, this selective surface catalysis phenomenon has also been confirmed by the simulated electric field distribution using FDTD method. Our results enlarge the metal nanostructure of PDSC reactions and provide a useful help to study the SERS and surface catalysis.