Surface-enhanced Raman scattering of crystal violets from periodic array of gold nanocylinders

Abstract

The periodic arrays of gold nanocylinder with 121 nm in diameter, 6.3 nm in gap, and 34 nm in thickness are fabricated on glass by electron-beam lithography and lift-off techniques. Some crystal violet molecules are coated on the array by using the dipping and drawing method. In addition, the surface-enhanced Raman scattering (SERS) spectra of these samples with and without gold nanocylinder arrays are characterized specifically. The largest enhancement factor is obtained when the excitation wavelength corresponds to the peak wavelength of localized surface plasmon resonance (LSPR). The density functional theory and the finite-difference time-domain method are used for the calculations of the extinction spectrum of the arrays and Raman spectra of the crystal violet, respectively. These results unambiguously demonstrate that the periodic arrays of gold nanocylinder have good and effective surface-enhanced properties for Raman scattering of crystal violets, and they also show that the excitation wavelength corresponding to the peak one of the LSPR is one of the major reasons causing SERS.

Keywords:

• surface-enhanced Raman scattering
• periodic gold nanocylinders
• electron-beam lithography and lift-off techniques
• crystal violet molecules

Acknowledgements

H M also acknowledges the funding from the Ministry of Education, Culture, Sports, Science, and Technology of Japan: KAKENHI Grant-in-Aid for Scientific Research no. 23225006, Nanotechnology Platform (Hokkaido University), and the Low-Carbon Research Network of Japan.

Funding

This work is financially supported by the National Natural Science Foundation of China [grant number 61275108], [grant number 50802083].