Large scale preparation of surface enhanced Raman spectroscopy substrates based on silver nanowires for trace chemical detection

Abstract

In this paper, a facile large-scale preparation of surface enhanced Raman spectroscopy (SERS) substrates based on silver nanowires has been developed. The SERS substrates can be easily and precisely obtained by filtering bulky amounts of silver nanostructures through hydrophilic filter membranes one time. The developed membranes can be expanded to commercial wafer-style filter membranes of large size (>47 mm in diameter). The as-prepared SERS substrates presented good uniformity and good performance for the detection of crystal violet (CV) and 1,2-di(4-pyridyl)ethylene (BPE). The relative standard deviations (RSD) were less than 5.5% (n ¼ 11) and 5.2% (n ¼ 11) for CV and BPE, respectively.The logarithm of characteristic SERS intensity plotted against CV and BPE concentrations presented a linear relationship over the ranges from 1.0 Â 10 À4 to 1.0 Â 10 À8 mol L À1 and from 5.0 Â 10 À4 to 5.0 Â 10 À9 mol L À1 , respectively. In the detection of natural water samples of river water, MembraneBio-Reactor (MBR) effluent and sewage disposal plant effluent, spiked with CV and BPE, the as-prepared SERS substrates also presented good performance, suggesting that such substrates possessed great potential in a broad range of analytical applications.

Cost Effective Silver Nanowire-Decorated Graphene Paper for Drop-On SERS Biodetection

“…An EF value of 4 × 10 6 was calculated, proving an enhancement ability of the same order of magnitude or higher than that from recently proposed low-cost disposable SERS substrates including those based on AgNWs assemblies [3,10,[43][44][45]. We tried to gain further insights into the high-quality SERS profiles of AgNWs@G-paper by theoretical simulation of the electromagnetic field distribution.…”

“…The higher average E-field value estimated at the graphene/AgNW interface hotspots, as compared to those formed at AgNWs interstitials ((|E|/|E0|)graphene/AgNW/(|E|/|E0|)AgNW/AgNW = 1.2), could be explained by taking into account the higher refractive index of graphene in comparison to other popular supports, which boosts the near field within the gap between metal and graphene, as shown in Figure 5c. An EF value of 4 × 10 6 was calculated, proving an enhancement ability of the same order of magnitude or higher than that from recently proposed low-cost disposable SERS substrates including those based on AgNWs assemblies [3,10,[43][44][45]. We tried to gain further insights into the high-quality SERS profiles of AgNWs@G-paper by theoretical simulation of the electromagnetic field distribution.…”

Catching Single Molecules with Plasmonic InGaN Quantum Dots

“…These spectral evolutions with reduced concentrations, although rarely discussed, were often observed on solid SERS substrates. [20,27,28] The differences in position and shape of SERS peaks can be understood by the two reasons: i) Since most of the peaks at 1500-1700 cm −1 stem from the broad base caused by twisted C-C vibration modes, [29] when the analytes are diluted, the sharp Raman peaks (from specific chemical bonds) become less pronounced, and eventually submerge in the wide-ranging base. ii) For the SERS spectra at concentrations approaching to the single-molecule level, the intensity (and/or frequency) of a Raman signal is no longer a population-averaged value, but sensitive to the individual molecular orientation relative to the binding site on the SERS substrate.…”