Zhang Zhiyuan, Li Zhaoxiang, Wang Luyao, Li Jinmeng, Pan Jie, Wang Shuyun, Zhang Chao, Li Zhen, Peng Qianqian, Xiu Xianwu
Opt Express. 2021 Oct 11;29(21):34552-34564. doi: 10.1364/OE.435662.
The composite substrate composed of precious metal, semiconductor and graphene has not only high sensitivity and uniform Raman signal but also stable chemical properties, which is one of the important topics in the field of surface-enhanced Raman scattering (SERS). In this paper, a sandwich SERS substrate based on tantalum oxide (TaO) is designed and fabricated. The substrate has high sensitivity, stable performance and high quantification capability. The composite substrate can achieve a high sensitivity Raman detection of crystal violet (CV) with a detection limit of 10 M and an enhancement factor of 1.5 × 10. This is the result of the synergistic effect of electromagnetic enhancement and chemical enhancement, in which the chemical enhancement is the cooperative charge transfer in the system composed of probe molecules, silver nanoparticles (AgNPs) and TaO, and the electromagnetic enhancement comes from the strong local surface plasmon resonance between the adjacent AgNPs. After exposing the composite substrate to the air for one month, the Raman signal did not weaken, indicating that the performance of the composite substrate is stable. In addition, there is an excellent linear relationship between the intensity of Raman characteristic peak and the concentration of probe molecules, which proves that the composite substrate has high quantification capability. In practical application, the composite SERS substrate can be used to detect harmful malachite green quickly and sensitively and has a broad application prospect in the field of food safety and chemical analysis.
由贵金属、半导体和石墨烯组成的复合基底不仅具有高灵敏度和均匀的拉曼信号，而且具有稳定的化学性质，这是表面增强拉曼散射（SERS）领域的重要课题之一。本文设计并制备了一种基于氧化钽（TaO）的三明治结构SERS基底。该基底具有高灵敏度、稳定的性能和高定量能力。该复合基底能够实现对结晶紫（CV）的高灵敏度拉曼检测，检测限为10⁻⁸ M，增强因子为1.5×10⁵。这是电磁增强和化学增强协同作用的结果，其中化学增强是由探针分子、银纳米颗粒（AgNPs）和TaO组成的体系中的协同电荷转移，电磁增强来自相邻AgNPs之间强烈的局部表面等离子体共振。将复合基底暴露在空气中一个月后，拉曼信号没有减弱，表明复合基底的性能稳定。此外，拉曼特征峰强度与探针分子浓度之间存在良好的线性关系，证明了复合基底具有高定量能力。在实际应用中，该复合SERS基底可用于快速、灵敏地检测有害的孔雀石绿，在食品安全和化学分析领域具有广阔的应用前景。
