Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Rd., Caugiay Dist., 100000 Hanoi, Vietnam.
Hanoi National University of Education, 136 Xuan Thuy, Caugiay Dist., 100000 Hanoi, Vietnam.
J Nanosci Nanotechnol. 2020 Mar 1;20(3):1928-1935. doi: 10.1166/jnn.2020.17136.
In this work, we present a novel fabrication method for making the surface-enhanced Raman scattering (SERS) probe based on silver (Ag) nano-dendrites which are grown and deposited on the end of multi-mode fibre core by a simple and low-cost laser-induced technique. The morphology of the Ag-nanoparticles (AgNPs) could be controlled by the experimental conditions such as laser power, illumination time, and concentration of the reaction solution. The morphology and chemical composition of SERS fibre probes are characterized by high-resolution scanning electron microscope (HR-SEM) and Energy dispersive X-ray spectroscopy (EDX), respectively. These results confirmed how the Ag nanostructures morphology is modified as a function of illumination time of laser irradiation, and the growth and deposition of Ag nanostructures occur only in the main laser-irradiated part on the end of multi-mode fibre core. The achieved SERS-activity substrates on the fibre probes are testing with the detection of low concentration of Rhodamine 6G aqueous solutions in the range of 10-10 M. This study shows that SERS activity coupled with Ag nano-dendrites substrate on the fibre probe has the best enhancement factor of 1.93×10 for Rhodamine 6G due to the creation of many of hot-spots for amplifying Raman signals by Ag nano-dendrite structures, which is a promising candidate with low-cost SERS probe of chemical compact optical fibre sensors for direct, rapid, real-time and non-destructive detection of chemical compounds in liquid environment.
在这项工作中，我们提出了一种新的制造方法，用于制作基于银（Ag）纳米枝晶的表面增强拉曼散射（SERS）探针，这些纳米枝晶通过简单且低成本的激光诱导技术生长并沉积在多模光纤芯的末端。Ag 纳米粒子（AgNPs）的形态可以通过实验条件（如激光功率、光照时间和反应溶液浓度）来控制。SERS 光纤探针的形貌和化学组成分别用高分辨率扫描电子显微镜（HR-SEM）和能谱（EDX）进行了表征。这些结果证实了 Ag 纳米结构形态如何随激光辐照时间的变化而改变，并且 Ag 纳米结构的生长和沉积仅发生在多模光纤芯末端的主要激光辐照部分。在光纤探针上实现的 SERS 活性衬底用在 10-10 M 范围内的低浓度罗丹明 6G 水溶液进行了测试。这项研究表明，由于 Ag 纳米枝晶结构产生了许多用于放大拉曼信号的热点，因此与光纤探针上的 Ag 纳米枝晶衬底相结合的 SERS 活性具有最佳的增强因子 1.93×10，这是一种具有成本效益的 SERS 探针，可用于直接、快速、实时和非破坏性地检测液体环境中的化合物。
