2011年2月，我室Bio—X交叉科学研究部罗毅教授研究组与低维物理与化学研究部王晓平教授合作在ACS NANO上发表题为Tuning Chemical Enhancement of SERS by Controlling the Chemical Reduction of Graphene Oxide Nanosheets的论文。

Source: ACS NANO Volume: 5 Issue: 2 Pages: 952-958 Published: FEB 2011

Yu XX (Yu, Xinxin)1, Cai HB (Cai, Hongbing)1, Zhang WH (Zhang, Wenhua)1, Li XJ (Li, Xinjing)2, Pan N (Pan, Nan)1, Luo Y (Luo, Yi)1,3, Wang XP (Wang, Xiaoping)1,2, Hou JG (Hou, J. G.)1

Addresses:
1. Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Hefei 230026, Anhui Peoples R China
2. Univ Sci & Technol China, Dept Phys, Hefei 230026, Anhui Peoples R China
3. Univ Sci & Technol China, Dept Chem Phys, Hefei 230026, Anhui Peoples R China
E-mail Addresses: yiluo@ustc.edu.cn, xpwang@ustc.edu.cn

Reprint Address: Luo, Y (reprint author), Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Hefei 230026, Anhui Peoples R China

Abstract:
Chemical enhancement is an important mechanism in surface-enhanced Raman spectroscopy. It is found that mildly reduced graphene oxide (MR-GO) nanosheets can significantly increase the chemical enhancement of the main peaks by up to 1 order of magnitude for adsorbed Rhodamine B (RhB) molecules, In comparison with the mechanically exfoliated graphene. The observed enhancement factors can be as large as similar to 10(3) and show clear dependence on the reduction time of graphene oxide, indicating that the chemical enhancement can be steadily controlled by specific chemical groups. With the help of X-ray photoelectron spectra, these chemical species are Identified and the origin of the observed large chemical enhancement can thus be revealed. It is shown that the highly electronegative oxygen species, which can introduce a strong local electric field on the adsorbed molecules, are responsible for the large enhancement. In contrast, the local defects generated by the chemical reduction show no positive correlation with the enhancement. Most importantly, the dramatically enhanced Raman spectra of RhB molecules on MR-GO nanosheets reproduce all important spectral fingerprints of the molecule with a negligible frequency shift. Such a unique noninvasive feature, along with the other intrinsic advantages, such as low cost, light weight, easy availability, and flexibility, makes the MR-GO nanosheets very attractive to a variety of practical applications.