Au-Ag bimetallic nanoparticles decorated silicon nanowires with fixed and dynamic hot spots for ultrasensitive 3D SERS sensing
Au-Ag bimetallic nanoparticles decorated silicon nanowires with fixed and dynamic hot spots for ultrasensitive 3D SERS sensing
复制标题
Au-Ag 双金属纳米颗粒装饰硅纳米线，具有固定和动态热点，用于超灵敏 3D SERS 传感
DOI：
10.1016/j.jallcom.2021.159136
复制
发表时间：
2021-03-02
影响因子：
6.2
通讯作者：
Gan, Ya
中科院分区：
文献类型：
--
作者：
Liao, Wenlong;Liu, Kunpng;Gan, Ya
三维（3D）表面增强拉曼散射（Sers）基底因其能提供大量的热点和指数陷阱靶而受到广泛的研究，硅纳米线（SiNWs）阵列因其易于制备而成为一种很有前途的候选基底。大多数情况下，基于硅纳米线的基底被修饰有纯Ag或Au纳米颗粒（NPs），具有上级等离子体特性和稳定性的Au-Ag双金属纳米颗粒（BMNP）很少被研究用于基于硅纳米线的Sers基底的制备。本文报道了一种制备Au-Ag BMNP修饰的SiNW作为3D Sers基底的方法，通过实验和理论模拟研究了Au-Ag BMNP的尺度和组成比例对Sers性能的影响。垂直排列的SiNWs表面包覆有致密的Au-Ag BMNP，通过形成固定和动态热点进一步提高了灵敏度，使用便携式拉曼光谱仪对SiNWs-AuAg上的R6 G的检测限可低至10-12 M。同时，由于Au-Ag BMNPs中Au和Ag原子的协同作用，制备的3D Sers基底表现出更高的Sers增强因子（EF）和抗氧化能力。考虑到简单的制备工艺和优异的性能，所制备的3D Sers基底可以潜在地应用于痕量分析物的超灵敏检测。(C)2021爱思唯尔有限公司版权所有。
Three-dimensional (3D) SERS substrates have being intensively investigated since they can afford sub-stantial hot spots and trap targets exponentially, silicon nanowires (SiNWs) array is a promising candidate due to its facile preparation. Most often, the SiNWs based substrates were decorated with pure Ag or Au nanoparticles (NPs), Au-Ag bimetallic NPs (BMNPs) with superior plasmonic properties and stabilities are rarely studied for the fabrication of SiNWs based SERS substrates. In this work, we reported a facile method to fabricate Au-Ag BMNPs decorated SiNWs as 3D SERS substrates, the effects of Au-Ag BMNPs scale and composition ratios on SERS performance were well investigated through experiments and theoretical simulations. The vertically aligned SiNWs coated with dense Au-Ag BMNPs further improved the sensitivity by forming fixed and dynamic hot spots, and the detection limit of R6G on SiNWs-AuAg can be as low as 10-12 M by using a portable Raman spectroscopy. Meanwhile, the prepared 3D SERS substrate showed a higher SERS enhancement factor (EF) and oxidation resistance ability due to the synergistic effect of Au and Ag atoms in Au-Ag BMNPs. Considering the facile fabrication process and excellent performances, the prepared 3D SERS substrate can be potentially applied for ultrasensitive detection of trace analytes. (C) 2021 Elsevier B.V. All rights reserved.