Geng Xiaoyuan, Wu Chen, Liu Siying, Han Yu, Song Liang, Zhang Yun
CAS Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou 350002 P. R. China
Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen 361021 P. R. China.
RSC Adv. 2021 Sep 22;11(50):31400-31407. doi: 10.1039/d1ra04473g. eCollection 2021 Sep 21.
Three-dimensional (3D) plasmonic nanostructures with nanoparticles that can be tuned have got a lot of attention in surface-enhanced Raman scattering (SERS) due to the unique 3D plasmonic coupling. Here, two nanoparticles, gold nanosphere (AuNS) and gold nanooctahedra (AuNO), were used to construct 3D hybrid SERS substrates to investigate the effect of nanoparticle spatial position on the SERS performance of the 3D nanostructure and to obtain 3D substrates with high SERS activity. And more hybrid combination possibilities were tested to explore the variation trend of hot spots generated when the nanoparticles were near. First, two-dimensional (2D) planar substrates were prepared using the air-liquid interface-assisted self-assembly method, to examine the effect of nanoparticle size on SERS performance. Then, 3D hybrid SERS substrates were further prepared layer by layer to discuss the effect of different combination methods within three layers on SERS performance. The optimized 3D hybrid substrate with the sandwich structure of AuNS/AuNO/AuNS performed the strongest SERS enhancement effect, whose intensity was 4.1 and 1.9 times that of AuNS/AuNS/AuNS and AuNO/AuNO/AuNO, respectively, and had good reproducibility (relative standard deviation (RSD) of 1.08%). Furthermore, the thiram molecular result showed that the prepared AuNS/AuNO/AuNS had good linear relationship ( of 0.991) and good molecule detection sensitivity (the minimum detection volume of thiram is 100 ppb), which demonstrated the great potential of the 3D hybrid SERS substrates in practical analysis.
具有可调控纳米粒子的三维（3D）等离子体纳米结构，由于其独特的三维等离子体耦合，在表面增强拉曼散射（SERS）中受到了广泛关注。在此，使用了两种纳米粒子，即金纳米球（AuNS）和金纳米八面体（AuNO），来构建三维混合SERS基底，以研究纳米粒子空间位置对三维纳米结构SERS性能的影响，并获得具有高SERS活性的三维基底。并且测试了更多的混合组合可能性，以探索纳米粒子靠近时产生的热点的变化趋势。首先，采用气液界面辅助自组装方法制备二维（2D）平面基底，以研究纳米粒子尺寸对SERS性能的影响。然后，进一步逐层制备三维混合SERS基底，以讨论三层内不同组合方法对SERS性能的影响。具有AuNS/AuNO/AuNS三明治结构的优化三维混合基底表现出最强的SERS增强效果，其强度分别是AuNS/AuNS/AuNS和AuNO/AuNO/AuNO的4.1倍和1.9倍，并且具有良好的重现性（相对标准偏差（RSD）为1.08%）。此外，福美双分子结果表明，制备的AuNS/AuNO/AuNS具有良好的线性关系（相关系数为0.991）和良好的分子检测灵敏度（福美双的最低检测体积为100 ppb），这证明了三维混合SERS基底在实际分析中的巨大潜力。
