Performance Improving Method of Aligned Silver Nanorod by Grafting Au@Ag Core–Shell Nanoparticles for Surface-Enhanced Raman Scattering

Abstract

A simple method for improving surface-enhanced Raman scattering (SERS) performance of aligned silver nanorod (Ag NR) array was investigated. This method was to construct a kind of hybrid substrate by grafting Au@Ag core-shell nanoparticles (NPs) into Ag NR array using poly (2-vinylphridine) (P2VPy) as a bridging agent. The hybrid substrate yielded excellent SERS performance as its detection limit improved from 10 À6 M to 10 À8 M using trans-1,2-bis(4-pyridyl) ethylene (BPE) as probe molecule, which was increased by two orders of magnitude compared with Ag NR array substrate. The signi¯cant improvement of SERS performance of Ag NR arrays was attributed to the addition of Au@Ag core-shell NPs. As a result of surface plasmon resonance generated by the interaction of electromagnetic (EM) (IAEM)¯led between NP and NR structures, increasing hotspots were found at the connections of NPs and NRs, the gaps of adjacent rods, and the gaps of two particles consequently. These results were validated by the¯nite di®erence time domain (FDTD) calculation. Besides, hybrid substrate shows good performance in stability and reproducibility. The proposed method was simple and robust, which promoted SERS performance of Ag NR array e®ectively, showing great potential in the application of SERS substrate fabrication and SERS-based bio-chemical sensing.

Ascorbic acid stabilised copper nanoclusters as fluorescent sensors for detection of quercetin

“…Metal nanoclusters (MNCs) as a novel uorescent material have been applied to detect toxic substances owing to excellent optical properties, stability and biocompatibility. [12][13][14][15][16] To date, a variety of metal nanoclusters have been successfully prepared through an etching synthesis method, 17 phase transfer synthesis method, 18 microwave-assisted synthesis method, 19 sonochemical synthesis method 20 and photoreduction synthesis method, 21 using Au, Ag, Pt and Cu NCs. [22][23][24][25][26][27] Compared to Ag and Au, Cu is an easily available and low-cost metal.…”

Au Nanoparticle/Graphene Oxide Composites Deposited on Au Nanorod Arrays as Substrates for Surface-Enhanced Raman Scattering Sensing

“…To optimize the SERS performance of AuNRAs modified by GO/AuNPs, 1,2-bis­(4-pyridyl)­ethylene (BPE) was selected as an analyte to evaluate the SERS activity. The LOD for different concentrations of BPE of various amounts of AuNPs on GO-modified AuNRAs was assessed, and the typical Raman “fingerprint” of BPE was observed as the peak at 1197.9, 1605.6, and 1634.7 cm –1 , corresponding, respectively, to the following BPE vibration modes: the CC stretching mode, the aromatic ring stretching mode, and the in-plane ring mode . We can see in Figure h–j that AuNRAs-GO/AuNPs-1, AuNRAs-GO/AuNPs-2, and AuNRAs-GO/AuNPs-3 possess the LOD for the BPE concentrations of 10 –10 , 10 –13 , and 10 –12 M, respectively.…”

Fabrication of Au Nanorods by the Oblique Angle Deposition Process for Trace Detection of Methamphetamine with Surface-Enhanced Raman Scattering

“…Figure 10 shows the average SERS spectra of BPE detected on the AuNRs array substrates deposited at θ = 80°, 82°, 84°, 86° and 88°, respectively. All the SERS spectra show three characteristic peaks of BPE [69] listed in Table 2: (C=C stretching mode), (aromatic ring stretching mode) and (in-plane ring mode). Among the five substrates shown in Figure 6, the best LOD, 10 −9 M, can be obtained for the nanostructures fabricated at deposition angle.…”