A facile seed growth method to prepare stable Ag@ZrO2 core-shell SERS substrate with high stability in extreme environments

Yongfeng Zhou; Pei Liang; De Zhang; Lisha Tang; Qianmin Dong; Shangzhong Jin; Dejiang Ni; Zhi Yu; Jiaming Ye

doi:10.1016/j.saa.2019.117676

A facile seed growth method to prepare stable Ag@ZrO₂ core-shell SERS substrate with high stability in extreme environments

Spectrochim Acta A Mol Biomol Spectrosc. 2020 Mar 5:228:117676. doi: 10.1016/j.saa.2019.117676. Epub 2019 Oct 24.

Authors

Yongfeng Zhou¹, Pei Liang², De Zhang³, Lisha Tang¹, Qianmin Dong¹, Shangzhong Jin¹, Dejiang Ni³, Zhi Yu³, Jiaming Ye⁴

Affiliations

¹ College of Optical and Electronic Technology, China Jiliang University, 310018, Hangzhou, China.
² College of Optical and Electronic Technology, China Jiliang University, 310018, Hangzhou, China. Electronic address: plianghust@gmail.com.
³ College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Key Laboratory of Horticultural Plant Biology, Ministry of Education, 430070, Wuhan, China.
⁴ Analysis and Testing Center, Yangtze Delta Region Institute of Tsinghua University, Jiaxing, 314006, China.

PMID: 31767414
DOI: 10.1016/j.saa.2019.117676

Abstract

A stable substrate is extraordinarily important for the trace detection of Surface Enhanced Raman Scattering technique. We have designed in this paper a simple seed growth method to prepare Ag@ZrO₂ core-shell nanoparticles as well as regulate the core-shell ratio by adjusted concentration of zirconium propoxides added. The shell thickness effect and spacing on SERS activities have been simulated in different finite time domains, which goes perfectly with those previous experiment results. With Ag@ZrO₂ core-shell nanoparticles adopted as the SERS substrate and R6G as molecular probe, the detection range could reach as great as 10^-8 M. The regression model, obtained through principal component analysis, is adopted for some rapid and precise detection; and the determination coefficient (R²) is going up to 0.9743, proving that the SERS substrate we have prepared has extremely high detection accuracy. To explore the stability of core-shell nanoparticles, we have taken both two different cases of strong acid solution as well as strong alkali solution for the core-shell nanoparticle etching, and this is how a SERS test could be carried out. These experimental results have indicated that the outer zirconia layer could keep the silver surface from oxidation and its stability is ensured, quite crucial for the applied SERS.

Keywords: Ag@ZrO(2) core-shell structure; Finite difference time domain simulation (FDTD); Principal component analysis (PCA); Quantitative detection; Seed growth method; Surface enhanced Raman scattering (SERS).