Quasi-Metal for Highly Sensitive and Stable Surface-Enhanced Raman Scattering

Zheng Tian; Hua Bai; Chao Chen; Yuting Ye; Qinghong Kong; Yahui Li; Wenhao Fan; Wencai Yi; Guangcheng Xi

doi:10.1016/j.isci.2019.08.040

Quasi-Metal for Highly Sensitive and Stable Surface-Enhanced Raman Scattering

iScience. 2019 Sep 27:19:836-849. doi: 10.1016/j.isci.2019.08.040. Epub 2019 Aug 27.

Authors

Zheng Tian¹, Hua Bai², Chao Chen³, Yuting Ye², Qinghong Kong⁴, Yahui Li², Wenhao Fan⁵, Wencai Yi⁶, Guangcheng Xi⁷

Affiliations

¹ Institute of Industrial and Consumer Product Safety, Chinese Academy of Inspection and Quarantine, Beijing 100176, P. R. China; School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, P. R. China.
² Institute of Industrial and Consumer Product Safety, Chinese Academy of Inspection and Quarantine, Beijing 100176, P. R. China.
³ School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
⁴ School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, P. R. China.
⁵ Physical Property Measurement Department, Beijing Center for Physical & Chemical Analysis, Beijing 100089, P. R. China.
⁶ School of Physics and Physical Engineering, Qufu Normal University, Qufu 273165, P. R. China.
⁷ Institute of Industrial and Consumer Product Safety, Chinese Academy of Inspection and Quarantine, Beijing 100176, P. R. China. Electronic address: xiguangcheng@caiq.org.cn.

Abstract

Compared with the noble-metal surface-enhanced Raman scattering (SERS) substrates activated by the surface plasmon resonance (SPR)-induced electromagnetic mechanism (EM), the relative low sensitivity and stability of the chemical mechanism (CM)-based substrates are the biggest obstacles to their applications. Herein, we report that quasi-metallic VO₂ nanosheet arrays can be used as a sensitive and stable SERS substrate. The lowest detectable limit of analyte adsorbed on the VO₂ nanosheets achieves 10^-10 M and the maximum Raman enhancement factor (EF) reaches 6.7 × 10⁷, which is comparable with that of the noble metals. The experimental and theoretical results demonstrate that the SERS performance of the VO₂ nanosheets comes from the strong interfacial interactions based on charge transfer and the vigorous SPR effects. Our research results demonstrate that quasi-metals are very promising SERS detection platforms and reveal that CM, like EM, contributes significantly to the SERS activity of quasi-metals.

Keywords: Electromagnetics; Materials Property; Nanomaterials; Physical Chemistry.