Fabrication of nano/microstructures for SERS substrates using an electrochemical method

Jingran Zhang; Tianqi Jia; Xiaoping Li; Junjie Yang; Zhengkai Li; Guangfeng Shi; Xinming Zhang; Zuobin Wang

doi:10.3762/bjnano.11.139

Fabrication of nano/microstructures for SERS substrates using an electrochemical method

Beilstein J Nanotechnol. 2020 Oct 16:11:1568-1576. doi: 10.3762/bjnano.11.139. eCollection 2020.

Authors

Jingran Zhang¹, Tianqi Jia¹, Xiaoping Li², Junjie Yang³, Zhengkai Li⁴, Guangfeng Shi¹, Xinming Zhang¹, Zuobin Wang¹

Affiliations

¹ College of Mechanical and Electric Engineering, Changchun University of Science and Technology, Changchun, Jilin 130000, P.R. China.
² Department of Pediatrics, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China.
³ Institute of Advanced Wear & Corrosion Resistant and Functional Materials, Jinan University, Guangzhou 510632, P.R. China.
⁴ School of Mechanical Engineering, Shandong University of Technology, Zibo, Shandong, 255000, P.R. China.

Abstract

Based on an electrochemical method, three-dimensional arrayed nanopore structures are machined onto a Mg surface. The structured Mg surface is coated with a thin gold (Au) film, which is used as a surface-enhanced Raman scattering (SERS) substrate. A rhodamine 6G (R6G) probe molecule is used as the detection agent for the SERS measurement. Different sizes of arrayed micro/nanostructures are fabricated by different treatment time using the electrochemical process. The topographies of these micro/nanostructures and the thickness of the Au film have an influence on the Raman intensity of the Mg substrate. Furthermore, when the thickness of Au film coating is held constant, the Raman intensity on the structured Mg substrates is about five times higher after a treatment time of 1 min when compared with other treatment times. The SERS enhancement factor ranges from 10⁶ to 1.75 × 10⁷ under these experimental conditions. Additionally, a 10^-6 mol·L^-1 solution of lysozyme was successfully detected using the Mg-Au nanopore substrates. Our low-cost method is reproducible, homogeneous, and suitable for the fabrication of SERS substrates.

Keywords: SERS substrate; electrochemical machining; gold (Au); lysozyme detection; magnesium (Mg); micro/nanopore; nano/microstructures.

Grants and funding

Jingran Zhang acknowledges the National Natural Science Foundation of China (grant No. 51905047), the China Postdoctoral Science Foundation (grant No. 2020M670824), the Jilin Postdoctoral Science Foundation and The Education Department of Jilin Province (grant No. JJKH20200750KJ). Junjie Yang acknowledges the Fundamental Research Funds for the Central Universities (grand No. 21620342) and National Key Research and Development Project (grand No. 2020YFC1107202).