Gold nanoparticle thin films fabricated by electrophoretic deposition method for highly sensitive SERS application
1 School of Electronic Science and Engineering, Southeast University, Nanjing, 210096, People's Republic of China
2 Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology, Ministry of Education, Nanjing, 210096, People's Republic of China
3 Suzhou Key Laboratory of Metal Nano-Optoelectronic Technology, Suzhou Research Institute of Southeast University, Suzhou, 215123, People's Republic of China
4 School of Materials Science and Engineering, Southeast University, Nanjing, 211189, People's Republic of China
5 Institute of Optics and Electronics, CAS, PO Box 350, Chengdu, Shuangliu, 610209, China
Nanoscale Research Letters 2012, 7:613 doi:10.1186/1556-276X-7-613Published: 6 November 2012
We report an electrophoretic deposition method for the fabrication of gold nanoparticle (GNP) thin films as sensitive surface-enhanced Raman scattering (SERS) substrates. In this method, GNP sol, synthesized by a seed-mediated growth approach, and indium tin oxide (ITO) glass substrates were utilized as an electrophoretic solution and electrodes, respectively. From the scanning electron microscopy analysis, we found that the density of GNPs deposited on ITO glass substrates increases with prolonged electrophoresis time. The films possess high mechanical adhesion strength and exhibit strong localized surface plasmon resonance (LSPR) effect by showing high SERS sensitivity to detect 1 × 10−7 M rhodamine 6 G in methanol solution. Finally, the relationship between Raman signal amplification capability and GNP deposition density has been further investigated. The results of our experiment indicate that the high-density GNP film shows relatively higher signal amplification capability due to the strong LSPR effect in narrow gap regions between the neighboring particles on the film.