Threading plasmonic nanoparticle strings with light

Herrmann, Lars O.; Valev, Ventsislav K.; Tserkezis, Christos; Barnard, J. S.; Kasera, Setu; Scherman, Oren A.; Aizpurua, Javier; Baumberg, Jeremy J.

doi:10.1038/ncomms5568

Cited by 149 publications

(179 citation statements)

References 34 publications

(39 reference statements)

Supporting

Mentioning

176

Contrasting

Order By: Relevance

“…11, both nanoparticle grating and nanoparticle chain extinction spectra show similar peaks at 410 nm attributable to either spherical silver nanoparticles or the out-of-plane dipole resonance of nanoplates, while the second peak at 515 nm is attributable to the in-plane dipole resonance of silver nanoplates [32]. For nanoparticle chains, the simulation demonstrated a weak coupling between silver nanoparticles from plasmon resonances, at around 665 nm with a broader peak at around 725 nm corresponding to the coupling between neighboring nanoparticle chains [33]. Plasmon resonance may account for much of the enhanced Raman signals as the surface plasmon frequency at 725 nm is approximately equal to the excitation wavelength of 785 nm [34,35].…”

Section: Numerical Simulationsmentioning

confidence: 72%

Two-Step Photonic Reduction of Controlled Periodic Silver Nanostructures for Surface-Enhanced Raman Spectroscopy

et al. 2015

View full text Add to dashboard Cite

Silver nanoparticle surface morphologies can be controlled using ultraviolet light or visible light-emitting diode (LED)-assisted photonic reduction of Ag ions in solution. Ultraviolet nanosecond laser interference lithography (LIL) is a cost-effective method for fabricating periodic structures in a polymer matrix, and in this work, we combine with photonic reduction to produce novel nanostructured substrates. Differing reduction times result in differing fringe widths and nanoparticle sizes, with nanoparticle shape gradually changing from spherical to plate-shaped with increasing (365 to 615 nm) excitation wavelengths. Such nanostructured substrates, when utilized for surface-enhanced Raman spectroscopy (SERS), realized analytical enhancement factors for naproxen of about 10 5 with plate-shaped nanoparticles, which was at least ten times greater than the enhancement afforded by spherical nanoparticles. A three-dimensional finite element method simulating localized surface plasmon resonance properties of these controlled silver structures demonstrated nanostructured plates effectively enhanced local electrical fields. Our results demonstrate that multi-wavelength photonic reduction integrated with LIL is an excellent means of providing sensitive substrates for SERS.

show abstract

Section: Numerical Simulationsmentioning

confidence: 72%

Two-Step Photonic Reduction of Controlled Periodic Silver Nanostructures for Surface-Enhanced Raman Spectroscopy

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The distribution of the population was estimated using TEM imagery analysis, Figure 2h, showing a distinct welded dimer (N = 2) population (≈75% yield) in agreement with the spectroscopic measurements. [7,8,10] For single gold nanorods synthesized using seed-mediated processes, the long wavelength limit of the LSP absorption peak is ≈1.2 µm, [11] similar to the CTP nanoantenna absorption peak in Figure 2c. The high quality factor (λ CTP /fwhm) CTP absorption peaks observed in Figure 2 are attributed to the CTP mode being insensitive to the relative orientation of the individual nanorods.…”

mentioning

confidence: 82%

“…[7] Similarly, experiments were carried out using gold nanorods, experimentally producing very polydisperse yields at near infrared wavelengths, indicating uncontrolled assembly and welding. The experimental wavelength tunability of this approach was ≈0.4 µm at near infrared wavelengths.…”

mentioning

confidence: 99%

Widely Tunable Infrared Plasmonic Nanoantennas Using Directed Assembly

Fontana

Nita

Charipar

et al. 2017

Advanced Optical Materials

View full text Add to dashboard Cite

tunable, monodisperse, high aspect ratio plasmonic nanoantennas.Very recently, molecules were used to link gold nanospheres into linear chains and the nanospheres were welded together following exposure to femtosecond laser pulses. The experimental wavelength tunability of this approach was ≈0.4 µm at near infrared wavelengths. [7] Similarly, experiments were carried out using gold nanorods, experimentally producing very polydisperse yields at near infrared wavelengths, indicating uncontrolled assembly and welding. [8] Further work refined this approach experimentally demonstrating discrete nanorod dimer nanoantennas with large and sharp absorption peaks, but used a slowly reacting aqueous based method. [9] Although this approach enabled high quality yields it is not practical for producing infrared nanoantennas due to the long assembly times and the large water absorption peaks which inhibit the ability to process and measure the suspensions at infrared wavelengths. The inability to experimentally direct and weld nanorod assemblies into higher order structures, while simultaneously producing high quality yields, has impeded progress into infrared wavelengths. If infrared plasmonic nanoantennas are to be efficiently realized, ushering in a fundamental nanotechnology building block, then these approaches must be generalized.The generalized experiment is illustrated in Figure 1a. Gold nanorods were concatenated end to end with dithiol molecules forming linear nanorod chains of controllable length (Figure 1a, background). The chains are welded together as they enter the femtosecond laser beam (red) producing tunable infrared plasmonic nanoantennas (Figure 1a, foreground). The experiment was monitored in situ with a spectrometer and white light source (white beam) orthogonal to the laser light (Experimental Section).Initially, aqueous suspensions of gold nanorods were stabilized with a bilayer of hexadecyltrimethylammonium bromide (CTAB) coating the cylindrical portion of the nanorods, Figure 1b. To enable the end to end assembly, the nanorods were then suspended in an acetonitrile:water (8:1) solution (Experimental Section). This allows the nanorods and nonpolar molecular linkers (1,6-hexanedithiol) to be costabilized in the same suspension by removing the outer most CTAB layer from the nanorods exposing the nonpolar tails of the CTAB Infrared plasmonic nanoantennas are key building blocks in nanotechnology. By coupling and confining light into spatial volumes below the diffraction limit, infrared plasmonic nanoantennas provide unique opportunities to sense and signal at nanometer length scales for energy harvesting, as light sources, and in nanomedicine applications. However, in contrast to their radio-and microwave counterparts, widespread use of plasmonic nanoantennas has been limited, due in part to the inability to synthesize these structures maintaining nanoscale precision in large batches with uniform yields. This communication describes a directed assembly approach to generate large quantities of infrared pl...

show abstract

“…6,9 In particular, by increasing the aspect ratio of nanorods, the second SPR can be shifted from the visible to the near infrared (NIR) range. [11][12][13] For instance, networks of partially fused gold nanoparticles showed very low-energy surface plasmon modes capable of supporting long-range and spectrally tunable propagation in nanoscale waveguides. 6,8 Recently, asymmetric networks of gold nanoparticles have been proposed as an interesting system to obtain versatile and multimodal plasmonic responses.…”

Section: Introductionmentioning

confidence: 99%

Laser generated gold nanocorals with broadband plasmon absorption for photothermal applications

et al. 2015

View full text Add to dashboard Cite

Gold nanoparticles with efficient plasmon absorption in the visible and near infrared (NIR) regions, biocompatibility and easy surface functionalization are of interest for photothermal applications. Herein we describe the synthesis and photothermal properties of gold "nanocorals" (AuNC) obtained by laser irradiation of Au nanospheres (AuNS) dispersed in liquid solution. AuNC are formed in two stages: by photofragmentation of AuNS, followed by spontaneous unidirectional assembly of gold nanocrystals. The whole procedure is performed without chemicals or templating compounds, hence the AuNC can be coated with thiolated molecules in one step. We show that AuNC coated with thiolated polymers are easily dispersed in an aqueous environment or in organic solvents and can be included in polymeric matrixes to yield a plasmonic nanocomposite. AuNC dispersions exhibit flat broadband plasmon absorption ranging from the visible to the NIR and unitary light-to-heat conversion. Besides, in vitro biocompatibility experiments assessed the absence of cytotoxic effects even at a dose as high as 100 μg mL(-1). These safe-by-designed AuNC are promising for use in various applications such as photothermal cancer therapy, light-triggered drug release, antimicrobial substrates, optical tomography, obscurant materials and optical coatings.

show abstract

Threading plasmonic nanoparticle strings with light

Cited by 149 publications

References 34 publications

Two-Step Photonic Reduction of Controlled Periodic Silver Nanostructures for Surface-Enhanced Raman Spectroscopy

Two-Step Photonic Reduction of Controlled Periodic Silver Nanostructures for Surface-Enhanced Raman Spectroscopy

Widely Tunable Infrared Plasmonic Nanoantennas Using Directed Assembly

Laser generated gold nanocorals with broadband plasmon absorption for photothermal applications

Contact Info

Product

Resources

About