Ordered array of Ag semishells on different diameter monolayer polystyrene colloidal crystals: An ultrasensitive and reproducible SERS substrate.

Zao Yi,Xiaoli Kang,Yougen Yi,Yong Yi,Gao Niu,Weitang Yao,Xin Ye,Jiangshan Luo,Tao Duan,Yongjian Tang,Weibin Zhang

doi:10.1038/srep32314

Abstract

Ag semishells (AgSS) ordered arrays for surface-enhanced Raman scattering (SERS) spectroscopy have been prepared by depositing Ag film onto polystyrene colloidal particle (PSCP) monolayer templates array. The diversified activity for SERS activity with the ordered AgSS arrays mainly depends on the PSCP diameter and Ag film thickness. The high SERS sensitivity and reproducibility are proved by the detection of rhodamine 6G (R6G) and 4-aminothiophenol (4-ATP) molecules. The prominent enhancements of SERS are mainly from the “V”-shaped or “U”-shaped nanogaps on AgSS, which are experimentally and theoretically investigated. The higher SERS activity, stability and reproducibility make the ordered AgSS a promising choice for practical SERS low concentration detection applications.

Highlights

Spin speed 1600 rad/min 2000 rad/min 2200 rad/min 2500 rad/min 2900 rad/min 3600 rad/min and gaps by combining magnetron sputtering and reactive ion etching[24]
The Ag semishells (AgSS) ordered arrays were successfully prepared by depositing Ag film onto monolayer polystyrene colloidal particle (PSCP) ordered array
The surface enhanced Raman scattering (SERS) properties of AgSS ordered arrays substrates can be controlled through the PSCP diameter and Ag film thickness

Summary

Result and Discussion

The high order monolayer PSCP films depend on many experiment parameters. Some parameters have been proven to be the most significant parameters, including the substrate wetting, solution concentration, velocity (spin speed) and spin acceleration[30,31]. As shown the Fig. 4(A–D), more Ag clusters deposited on the PSCP and the V-shaped gap for the 40 nm Ag film than for the other thicknesses, which will contribute to the enhancement in SERS performance. Detailed studies of all the geometric parameters influencing the calculations results are beyond the scope of the present work, and will be discussed in detail in the future research

Conclusions

Findings

Author Contributions

Additional Information