Rapid Fabrication of a Flexible and Transparent Ag Nanocubes@PDMS Film as a SERS Substrate with High Performance

作者：Limin Li, Wee Shong Chin · 发表于：ACS Applied Materials & Interfaces · 年份：2020 · DOI：10.1021/acsami.0c07178 · 被引用次数：221 · 研究领域：Gold and Silver Nanoparticles Synthesis and Applications、Biosensors and Analytical Detection、Advanced biosensing and bioanalysis techniques

Flexible and transparent surface-enhanced Raman scattering (SERS) substrates have long been sought-after for nondestructive detection of analytes on nonplanar surfaces, but there is still a lack of one convenient and robust way to fabricate such SERS substrates rapidly. Herein, we demonstrate the fabrication of a high-performance SERS substrate consisting of plasmonic Ag nanocube (Ag NC) arrays anchored onto a flexible transparent poly(dimethylsiloxane) (PDMS) membrane. Through a simple organic/water interfacial self-assembly method, arrays of presynthesized Ag NCs are obtained and directly retrieved onto the PDMS membrane without the aid of rigid substrates (e.g., Si wafers or glass slides). The plasmonic Ag NC arrays can produce strong electromagnetic enhancement, achieving high SERS enhancement factor (∼3.43 × 10 6 ) and ideal detection capability for methylene blue (MB) and Rhodamine 6G (R6G) at respective trace amounts of 10 –10 and 10 –9 M. Moreover, without the need to transfer from substrate to substrate, the regular Ag NC arrays are kept intact, thereby yielding a good reproducibility (RSD ∼12%). We demonstrate further that our as-fabricated SERS substrate displays ideal selectivity toward different kinds of analyte molecules (R6G, crystal violet (CV), and MB) based on principal component analysis. The PDMS membrane owns excellent transparency and flexibility; thus, the substrate enables the conformal contact with nonplanar surfaces and allows the penetration of a la...