A tunable Au core–Ag shell nanoparticle tip for tip-enhanced spectroscopy

Kim, Woong; Kim, Nara; Lee, Eunbyoul; Kim, Duckhoe; Kim, Zee Hwan; Park, Chong-Yun

doi:10.1039/c6an00035e

Cited by 12 publications

(11 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The radius of the filaments can be as small as 3 nm. Recently, Kim and co-workers used single DNA strands to tether 5-nm Au NPs onto AFM probes and then transferred the tips into enhancing solutions to make core–shell Au–Ag NPs and Au nanostars in high yields . TERS and tip-enhanced fluorescence measurements were successfully conducted with these tips, but the low reproducibility of the geometry, such as the particle shape and orientation of spikes, resulted in a large tip-to-tip variation in enhancement factors.…”

Section: Nanoantenna Design Fabrication and Characterizationmentioning

confidence: 67%

Advances in Tip-Enhanced Near-Field Raman Microscopy Using Nanoantennas

et al. 2017

View full text Add to dashboard Cite

Tip-enhanced near-field Raman microscopy spectroscopy is a scanning probe technique that is capable of providing vibrational spectroscopic information on single nanoobjects and surfaces at (sub-) nanometer spatial resolution and high detection sensitivity. In this review, we first illustrate the physical principle of optical nanoantennas used in tip-enhanced near-field Raman microscopy and tip-enhanced Raman scattering (TERS) to efficiently couple light to Raman excitations on nanometer length scales. Although the antennas' electric near-field distributions are commonly understood to determine the spatial resolution, recent experiments showing subnanometer-resolved optical images put this understanding into question. This is because such images enter a regime in which classical electrodynamical descriptions might no longer be applicable and quantum plasmonic and atomistic effects could become relevant. After summarizing the current understanding of plasmonic phenomena at extremely short length scales, we discuss the different mechanisms contributing to the signal enhancement. In addition to the known contributions from electric-field and chemical enhancement, several new models have been proposed very recently that could provide important guidelines for the optimization of TERS experiments. We then review recent developments in the areas of antenna design, fabrication, and characterization. Finally, we briefly highlight recent applications to illustrate future directions of tip-enhanced near-field Raman microscopy and TERS.

show abstract

Section: Nanoantenna Design Fabrication and Characterizationmentioning

confidence: 67%

Advances in Tip-Enhanced Near-Field Raman Microscopy Using Nanoantennas

et al. 2017

View full text Add to dashboard Cite

show abstract

“…To prevent or restrain the randomness of hot spot localization (unavoidable in metal films) and improve the manufacturing reproducibility of AFM‐TERS tips, selective decoration of tip apexes with Ag, Au, and Au–Ag core–shell NPs was performed by means of laser‐induced synthesis, dielectrophoresis, or applying the pick‐up process on dendron‐modified AFM tips followed by the growth of an Ag shell or Au spikes . Microfabrication methods (FIB milling, photolithography, …) also attracted much interest due to their ability to manufacture highly reproducible nanostructures with relatively high electromagnetic field enhancements.…”

Section: Experimental Developments In Tersmentioning

confidence: 99%

Tip‐Enhanced Raman Spectroscopy: A Tool for Nanoscale Chemical and Structural Characterization of Biomolecules

Bonhommeau

Lecomte

2017

ChemPhysChem

View full text Add to dashboard Cite

Due to its high molecular sensitivity and spatial optical resolution down to sub‐nanometer values, tip‐enhanced Raman spectroscopy (TERS) has emerged as a powerful microscopy technique for nanoscale characterization. Progress in TERS instrumentation and in the manufacturing of efficient TERS tips allow for chemical and structural analysis under various experimental conditions (different wavelengths, substrates, and surrounding media). Many biological species have been examined by using this technique. Nucleic acids (individual nucleobases, DNA, and RNA) can show specific TERS features that reveal their composition, conformation, and defects. TERS studies on peptides and proteins (such as amyloid fibrils) provide relevant information on their morphology and structure, leading to valuable insight to their functions and behavior. Finally, lipid layers and membranes, viruses, bacteria, and cells can also be finely characterized. Generalizing TERS measurements in liq‐ uid medium to study biological systems is the main future challenge.

show abstract

“…Groups have demonstrated fabrication of plasmonic probes by mounting Au nanoparticles onto nonplasmonic tips. ,, You et al reported using alternating current dielectrophoresis for grafting individual Ag nanowires to W wires with demonstrated TERS activity . In addition, Kim et al demonstrated in situ growth of a Ag-coated Au nanoparticle at the apex of an AFM tip . Finally, electrochemical deposition of plasmonic nanoparticles at the conductive apex of a nanoprobe enables reproducible tips whose optical properties can be tailored. , Such methods allow researchers to tailor physical properties of constructed tips, such as plasmon frequency, for particular applications.…”

Section: Tersmentioning

confidence: 99%

“…143 In addition, Kim et al demonstrated in situ growth of a Ag-coated Au nanoparticle at the apex of an AFM tip. 158 Finally, electrochemical deposition of plasmonic nanoparticles at the conductive apex of a nanoprobe enables reproducible tips whose optical properties can be tailored. 159,160 Such methods allow researchers to tailor physical properties of constructed tips, such as plasmon frequency, for particular applications.…”

Section: Tip Fabricationmentioning

confidence: 99%

Ultrahigh-Vacuum Tip-Enhanced Raman Spectroscopy

Pozzi¹,

Goubert²,

Chiang³

et al. 2016

Chem. Rev.

136

107

View full text Add to dashboard Cite

Molecule-surface interactions and processes are at the heart of many technologies, including heterogeneous catalysis, organic photovoltaics, and nanoelectronics, yet they are rarely well understood at the molecular level. Given the inhomogeneous nature of surfaces, molecular properties often vary among individual surface sites, information that is lost in ensemble-averaged techniques. In order to access such site-resolved behavior, a technique must possess lateral resolution comparable to the size of surface sites under study, analytical power capable of examining chemical properties, and single-molecule sensitivity. Tip-enhanced Raman spectroscopy (TERS), wherein light is confined and amplified at the apex of a nanoscale plasmonic probe, meets these criteria. In ultrahigh vacuum (UHV), TERS can be performed in pristine environments, allowing for molecular-resolution imaging, low-temperature operation, minimized tip and molecular degradation, and improved stability in the presence of ultrafast irradiation. The aim of this review is to give an overview of TERS experiments performed in UHV environments and to discuss how recent reports will guide future endeavors. The advances made in the field thus far demonstrate the utility of TERS as an approach to interrogate single-molecule properties, reactions, and dynamics with spatial resolution below 1 nm.

show abstract

A tunable Au core–Ag shell nanoparticle tip for tip-enhanced spectroscopy

Cited by 12 publications

References 36 publications

Advances in Tip-Enhanced Near-Field Raman Microscopy Using Nanoantennas

Advances in Tip-Enhanced Near-Field Raman Microscopy Using Nanoantennas

Tip‐Enhanced Raman Spectroscopy: A Tool for Nanoscale Chemical and Structural Characterization of Biomolecules

Ultrahigh-Vacuum Tip-Enhanced Raman Spectroscopy

Contact Info

Product

Resources

About