title: A comparative study of gold nanocubes, octahedra, and rhombic dodecahedra as highly sensitive SERS substrates.
abstract: Gold nanocubes, octahedra, and rhombic dodecahedra with roughly two sets of particle sizes have been successfully synthesized via a seed-mediated growth approach. All six samples were analyzed for comparative surface-enhanced Raman scattering (SERS) activity. All of these Au nanostructures were found to yield strong enhancement at a thiophenol concentration of 10(-7) M and are excellent SERS substrates. Rhombic dodecahedra with a rhombus edge length of 32 nm showed significantly better enhancement than the other samples and can reach a detection limit of 10(-8) M. Simulations of the binding energies of thiophenol on the different faces of gold and electric near-field intensities of these nanocrystals have been performed to evaluate the experimental results. Superior SERS activity of these nanocrystals can be expected toward the detection of many other molecules.
authors.affiliation: Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Hsin-Lun
authors.initials: HL
authors.lastname: Wu
authors.forename: Huei-Ru
authors.initials: HR
authors.lastname: Tsai
authors.forename: Yun-Ting
authors.initials: YT
authors.lastname: Hung
authors.forename: Ka-Un
authors.initials: KU
authors.lastname: Lao
authors.forename: Ching-Wen
authors.initials: CW
authors.lastname: Liao
authors.forename: Pei-Ju
authors.initials: PJ
authors.lastname: Chung
authors.forename: Jer-Shing
authors.initials: JS
authors.lastname: Huang
authors.forename: I-Chia
authors.initials: IC
authors.lastname: Chen
authors.forename: Michael H
authors.initials: MH
authors.lastname: Huang