Template-confined assembly of Ag nanocubes: An approach to fabricate SERS substrate with good performance

Jiaqi Liu; Chunning Chen; Jiaxin Lu; Yalei Wang; Jingtong Zhai; Hongkun Zhao; Nan Lu

doi:10.1016/j.talanta.2023.125442

Template-confined assembly of Ag nanocubes: An approach to fabricate SERS substrate with good performance

Talanta. 2024 Mar 1:269:125442. doi: 10.1016/j.talanta.2023.125442. Epub 2023 Nov 24.

Authors

Jiaqi Liu¹, Chunning Chen¹, Jiaxin Lu¹, Yalei Wang¹, Jingtong Zhai¹, Hongkun Zhao¹, Nan Lu²

Affiliations

¹ State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China.
² State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China. Electronic address: luenan@jlu.edu.cn.

PMID: 38029608
DOI: 10.1016/j.talanta.2023.125442

Abstract

Surface-enhanced Raman scattering (SERS) is an important analytical technique. Its detection sensitivity and reproducibility depend on the density and distribution of SERS hotspots. Self-assembly is an efficient method to produce of SERS substrates due to its easy accessibility. However, the assembled defects can hardly be avoided on large area, which could lower the density and uniformity of the hotspots, leading to poor SERS performance. Herein, we report a method to reduce the defects by taking a patterned substrate as template to confine the assembly of Ag nanocubes. The template was prepared based on the combination of photo lithography and self-assembly. Confined by the template, the Ag nanocubes were assembled closely in each dots of the pattern. The limit of detection (LOD) is down to 3.42 × 10^-17 M and the enhanced factor (EF) is up to 3.44 × 10¹⁰ on the prepared substrate for detecting rhodamine 6G (R6G). In addition, the relative standard deviation (RSD) of the different substrates is 8.75 %. The assembled Ag nanocubes exhibits high sensitivity and reproducibility as SERS substrate, which are contributed by the formation of high-density and uniform hotspots. The prepared substrate can be used for detecting trace amounts of melamine in milk with LOD of 2.06 × 10^-7 M and RSD of 6.91 %, so the substrate is applicable for analyzing various analytes.

Keywords: Confined assembly; High-density; Hotspots; Patterned substrate; SERS substrate.