Characterization of Tetrahexahedral Gold Nanocrystals: A Combined Study by Surface-Enhanced Raman Spectroscopy and Computational Simulations

Abstract

Tetrahexahedral (THH) and elongated tetrahexahedral (ETHH) gold nanocrystals (NCs) were fabricated and were studied for their unique surface plasmon (SP) excitation. UV–vis absorption spectra and surface-enhanced Raman scattering (SERS) were introduced to experimentally investigate the far-field optical properties and near-field enhancement ability of nanoparticles. Calculation of electric field distribution on the basis of three-dimensional finite-difference time domain (3D-FDTD) method revealed that the E-field enhancement is largely confined to tips with strong dependences on geometry of tip and polarization of incident light. Enhancement factors were estimated, and several influence factors such as coupling effect were mentioned with discussion for the potential advantages of polyhedron-like structure in plasmon-related application.

One-pot synthesis affords perfectly six-fold symmetrical Au microsnowflakes for excellent electrochemical biosensing and surface-enhanced Raman scattering assays

“…10c, we nd that the Raman shi was changed and the Raman intensity was enhanced in the SERS spectra on the two different Au substrates. 20 The n CC band at 1594 cm À1 shied to 1587 and the d CH band shied from 1183 cm À1 to 1175 as a result of bonding and electronic structure changes. 10, the predominant bands in the spectrum of solid PMBA are located at 1099, 1183 and 1594 cm À1 , which are assigned to a1 modes of n CS , d CH , and n CC , respectively.…”

“…12 Besides adenosine is the core of the cell's energy-containing compound, ATP. 20 So the detection limit of adenosine may range differently due to the various Au nanostructures as SERS substrates. Many scholars have reported lots of achievements in electrochemical analysis.…”

Enantiomeric separations of chiral pharmaceuticals using chirally modified tetrahexahedral Au nanoparticles

“…The planes revealed by the high resolution image in Figure 1C are spaced along the [100] direction. Although the facets orientation have not been determined in this work, prior work shows that they are achiral, high Miller index planes [13][14][15][16][17] . The UV-vis spectra are also…”

“…, and [740][13][14][15][16][17] . Au NPs with high-index planes can have high densities of atoms or steps which result in high surface energy.…”

Influenced of electron density on plasmonic behavior of coupled AU nanostructures

“…These features include ratio of absorption to scattering, number of plasmon modes, as well as its resonance position, and the bandwidth. [66][67][68] Clearly, as the size of the nanostructure is increased, the LSPR will red shifted due to retardation of the collective oscillation of electrons. Similar results can be observed as the refractive index of the nanoparticle's surrounding increased.…”