Porous carbon nanowire array for surface-enhanced Raman spectroscopy

Abstract Surface-enhanced Raman spectroscopy (SERS) is a powerful tool for vibrational spectroscopy as it provides several orders of magnitude higher sensitivity than inherently weak spontaneous Raman scattering by exciting localized surface plasmon resonance (LSPR) on metal substrates. However, SERS can be unreliable for biomedical use since it sacrifices reproducibility, uniformity, biocompatibility, and durability due to its strong dependence on “hot spots”, large photothermal heat generation, and easy oxidization. Here, we demonstrate the design, fabrication, and use of a metal-free (i.e., LSPR-free), topologically tailored nanostructure composed of porous carbon nanowires in an array as a SERS substrate to overcome all these problems. Specifically, it offers not only high signal enhancement (~106) due to its strong broadband charge-transfer resonance, but also extraordinarily high reproducibility due to the absence of hot spots, high durability due to no oxidization, and high compatibility to biomolecules due to its fluorescence quenching capability.

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Composite Structure Based on Gold-Nanoparticle Layer and HMM for Surface-Enhanced Raman Spectroscopy Analysis

Nanomaterials ◽

10.3390/nano11030587 ◽

2021 ◽

Vol 11 (3) ◽

pp. 587

Author(s):

Zirui Wang ◽

Yanyan Huo ◽

Tingyin Ning ◽

Runcheng Liu ◽

Zhipeng Zha ◽

...

Keyword(s):

Gold Nanoparticle ◽

Surface Plasmon ◽

Composite Structure ◽

Surface Enhanced Raman Spectroscopy ◽

Localized Surface Plasmon ◽

Sers Substrate ◽

Nanoparticle Layer ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Plasmon Polaritons

Hyperbolic metamaterials (HMMs), supporting surface plasmon polaritons (SPPs), and highly confined bulk plasmon polaritons (BPPs) possess promising potential for application as surface-enhanced Raman scattering (SERS) substrates. In the present study, a composite SERS substrate based on a multilayer HMM and gold-nanoparticle (Au-NP) layer was fabricated. A strong electromagnetic field was generated at the nanogaps of the Au NPs under the coupling between localized surface plasmon resonance (LSPR) and a BPP. Additionally, a simulation of the composite structure was assessed using COMSOL; the results complied with those achieved through experiments: the SERS performance was enhanced, while the enhancing rate was downregulated, with the extension of the HMM periods. Furthermore, this structure exhibited high detection performance. During the experiments, rhodamine 6G (R6G) and malachite green (MG) acted as the probe molecules, and the limits of detection of the SERS substrate reached 10−10 and 10−8 M for R6G and MG, respectively. Moreover, the composite structure demonstrated prominent reproducibility and stability. The mentioned promising results reveal that the composite structure could have extensive applications, such as in biosensors and food safety inspection.

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Reusable Surface-Enhanced Raman Spectroscopy Substrates Made of Silicon Nanowire Array Coated with Silver Nanoparticles Fabricated by Metal-Assisted Chemical Etching and Photonic Reduction

Nanomaterials ◽

10.3390/nano9111531 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1531 ◽

Cited By ~ 2

Author(s):

Shi Bai ◽

Yongjun Du ◽

Chunyan Wang ◽

Jian Wu ◽

Koji Sugioka

Keyword(s):

Silver Nanoparticles ◽

Chemical Etching ◽

Silicon Nanowire ◽

Nanowire Array ◽

Surface Enhanced Raman Spectroscopy ◽

Sers Substrate ◽

Silicon Nanowire Array ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Metal Assisted Chemical Etching

Surface-enhanced Raman spectroscopy (SERS) has advanced over the last four decades and has become an attractive tool for highly sensitive analysis in fields such as medicine and environmental monitoring. Recently, there has been an urgent demand for reusable and long-lived SERS substrates as a means of reducing the costs associated with this technique To this end, we fabricated a SERS substrate comprising a silicon nanowire array coated with silver nanoparticles, using metal-assisted chemical etching followed by photonic reduction. The morphology and growth mechanism of the SERS substrate were carefully examined and the performance of the fabricated SERS substrate was tested using rhodamine 6G and dopamine hydrochloride. The data show that this new substrate provides an enhancement factor of nearly 1 × 108. This work demonstrates that a silicon nanowire array coated with silver nanoparticles is sensitive and sufficiently robust to allow repeated reuse. These results suggest that this newly developed technique could allow SERS to be used in many commercial applications.

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Three-dimensional donut-like gold nanorings with multiple hot spots for surface-enhanced raman spectroscopy

Nanotechnology ◽

10.1088/1361-6528/28/4/045303 ◽

2016 ◽

Vol 28 (4) ◽

pp. 045303 ◽

Cited By ~ 13

Author(s):

Mengjie Zheng ◽

Xupeng Zhu ◽

Yiqin Chen ◽

Quan Xiang ◽

Huigao Duan

Keyword(s):

Raman Spectroscopy ◽

Hot Spots ◽

Three Dimensional ◽

Surface Enhanced Raman Spectroscopy ◽

Surface Enhanced ◽

Surface Enhanced Raman

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Application of Doehlert Matrix for an Optimized Preparation of a Surface-Enhanced Raman Spectroscopy (SERS) Substrate Based on Silicon Nanowires for Ultrasensitive Detection of Rhodamine 6G

Applied Spectroscopy ◽

10.1177/0003702819881222 ◽

2019 ◽

Vol 74 (2) ◽

pp. 168-177 ◽

Cited By ~ 4

Author(s):

Awatef Ouhibi ◽

Maroua Saadaoui ◽

Nathalie Lorrain ◽

Mohammed Guendouz ◽

Noureddine Raouafi ◽

...

Keyword(s):

Raman Spectroscopy ◽

Silver Nitrate ◽

Silicon Nanowires ◽

Rhodamine 6G ◽

Surface Enhanced Raman Spectroscopy ◽

Influential Factor ◽

Metallic Surface ◽

Sers Substrate ◽

Surface Enhanced ◽

Surface Enhanced Raman

In this work, we combined a hierarchical nano-array effect of silicon nanowires (SiNWs) with a metallic surface of silver nanoparticles (AgNPs) to design a surface-enhanced Raman spectroscopy (SERS) scattering substrate for sensitive detection of Rhodamine 6G (R6G) which is a typical dye for fluorescence probes. The SiNWs were prepared by Metal-Assisted Chemical Etching (MACE) of n-Si (100) wafers. The Doehlert design methodology was used for planning the experiment and analyzing the experimental results. Thanks to this methodology, the R6G SERS response has been optimized by studying the effects of the silver nitrate concentration, silver nitrate and R6G immersion times and their interactions. The immersion time in R6G solution stands out as the most of influential factor on the SERS response.

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Identification and Characterization of Artists' Red Dyes and Their Mixtures by Surface-Enhanced Raman Spectroscopy

Applied Spectroscopy ◽

10.1366/000370207781745838 ◽

2007 ◽

Vol 61 (9) ◽

pp. 994-1000 ◽

Cited By ~ 46

Author(s):

Alyson V. Whitney ◽

Francesca Casadio ◽

Richard P. Van Duyne

Keyword(s):

Raman Spectroscopy ◽

Surface Enhanced Raman Spectroscopy ◽

Localized Surface Plasmon ◽

Carminic Acid ◽

Sers Substrates ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Lac Dye ◽

Silver Island

Silver film over nanospheres (AgFONs) were successfully employed as surface-enhanced Raman spectroscopy (SERS) substrates to characterize several artists' red dyes including: alizarin, purpurin, carminic acid, cochineal, and lac dye. Spectra were collected on sample volumes (1 × 10−6 M or 15 ng/μL) similar to those that would be found in a museum setting and were found to be higher in resolution and consistency than those collected on silver island films (AgIFs). In fact, to the best of the authors' knowledge, this work presents the highest resolution spectrum of the artists' material cochineal to date. In order to determine an optimized SERS system for dye identification, experiments were conducted in which laser excitation wavelengths were matched with correlating AgFON localized surface plasmon resonance (LSPR) maxima. Enhancements of approximately two orders of magnitude were seen when resonance SERS conditions were met in comparison to non-resonance SERS conditions. Finally, because most samples collected in a museum contain multiple dyestuffs, AgFONs were employed to simultaneously identify individual dyes within several dye mixtures. These results indicate that AgFONs have great potential to be used to identify not only real artwork samples containing a single dye but also samples containing dyes mixtures.

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