Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• aqueous dispersion of AgNPs, which exhibit a higher absorption in the region of Raman excitation wavelength (514.5 nm). The reported phenomenon is depended on the size and shape of AgNPs and on the wavelength of the surface plasmon, characteristic for particular AgNPs. The performed reabsorption

Rapid controlled synthesis of gold–platinum nanorods with excellent photothermal properties under 808 nm excitation

• Jialin Wang,
• Qianqian Duan,
• Min Yang,
• Boye Zhang,
• Li Guo,
• Pengcui Li,
• Wendong Zhang and
• Shengbo Sang

Beilstein J. Nanotechnol. 2021, 12, 462–472, doi:10.3762/bjnano.12.37

• conversion efficiency (PCE) due to local surface plasmon resonance (LSPR). Studies on different gold–platinum (Au–Pt) bimetal nanoparticles exhibiting the LSPR effect have provided a new idea for the synthesis of excellent PTAs. But there is no simple and scalable method for the controllable synthesis of Au

• . Keywords: AuNRs; local surface plasmon resonance (LSPR); photothermal conversion efficiency; photothermal transduction agents; platinum; Introduction On the surface of noble metal nanoparticles, when the wavelength of incident light resonates with the light absorption wavelength of the nanoparticles, a

• absorption in the UV–vis range. Hence, these nanoparticles can be applied as excellent PTAs. The PCE of PTAs is directly related to the light absorption capacity. For plasmon nanoparticles, their absorption will be significantly enhanced when the illumination laser wavelength is equal to their LSPR

A review on nanostructured silver as a basic ingredient in medicine: physicochemical parameters and characterization

• Gabriel M. Misirli,
• Kishore Sridharan and
• Shirley M. P. Abrantes

Beilstein J. Nanotechnol. 2021, 12, 440–461, doi:10.3762/bjnano.12.36

• AgNPs with light leads to surface plasmon resonance (SPR) effect when the incident light frequency coincides with the frequency of the oscillating electrons on the surface. The surface of AgNPs stores the conducting electrons inside the particles and establishes a restorative force which creates a

• dipolar surface plasmon frequency [61][62]. SPR can be modulated by controlling the shape of AgNPs, which in turn controls the ways in which the electrons oscillate. The light is spread and absorbed inside the nanostructure and intensifies the local electric fields [63]. In general, smaller nanoparticles

• term "plasmon" was introduced by Pines and Bohm (1952) and it means, in a very brief way, that electrons move as a group inside of a metal. Together, the electrons alternately flow back and forth while being attracted to the positive ions, which make up the crystal structure, and are repelled when they

The patterning toolbox FIB-o-mat: Exploiting the full potential of focused helium ions for nanofabrication

• Victor Deinhart,
• Lisa-Marie Kern,
• Jan N. Kirchhof,
• Sabrina Juergensen,
• Joris Sturm,
• Enno Krauss,
• Thorsten Feichtner,
• Sviatoslav Kovalchuk,
• Michael Schneider,
• Dieter Engel,
• Bastian Pfau,
• Bert Hecht,
• Kirill I. Bolotin,
• Stephanie Reich and
• Katja Höflich

Beilstein J. Nanotechnol. 2021, 12, 304–318, doi:10.3762/bjnano.12.25

• combined in a straightforward manner, for example, by stacking. Applications of such materials may rely on (coupled) material excitations, such as plasmon polaritons in gold nanostructures [2], on physical properties, such as the exceptionally high mechanical stability of suspended graphene [3], or on

• -crystalline gold constitute an ideal platform for plasmonic applications due to the lack of scattering losses at grain boundaries and surface roughness [56]. In nanostructured gold, collective excitations of the free electron gas may occur under the incidence of visible light [2]. These plasmon polaritons of

Doxorubicin-loaded gold nanorods: a multifunctional chemo-photothermal nanoplatform for cancer management

• Uzma Azeem Awan,
• Abida Raza,
• Shaukat Ali,
• Rida Fatima Saeed and
• Nosheen Akhtar

Beilstein J. Nanotechnol. 2021, 12, 295–303, doi:10.3762/bjnano.12.24

• -dispersion. A CTAB bilayer remained non-covalently bound onto the GNRs surface to maintain the stability of the final product. The longitudinal localized plasmon resonance (LSPR) and the transverse plasmon resonance (TSPR) of the prepared GNRs were found to be 780 and 526 nm, respectively. TEM images display

A review on the green and sustainable synthesis of silver nanoparticles and one-dimensional silver nanostructures

• Sina Kaabipour and
• Shohreh Hemmati

Beilstein J. Nanotechnol. 2021, 12, 102–136, doi:10.3762/bjnano.12.9

• [80][81][82]. For instance, the utilization of AgNPs in bone cement is meant to prevent bacterial infection while sustaining the mechanical strength of the cement connected to the prosthesis [82]. AgNPs have also demonstrated significant optical properties. They possess substantial surface plasmon

• -field effect and localized surface plasmon resonance (LSPR) [32]. There are several applications in which use of 1D silver nanostructures such as nanowires (NWs) and nanorods (NRs) (at the same concentration) are preferred to other nanostructures due to stronger conductivity. For instance, 1D silver

• concentration inside the reverse micelles [235]. AOT-microemulsions have been the most common microemulsions for the preparation of micelles [152]. However, this method may result in the synthesis of AgNPs with weak surface plasmon characteristics due to a broad surface plasmon band [152]. 2.2.3 Chemical vapor

The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• is an increase in the catalytic activity when compared to the monometallic Au or Cu nanoparticles [3]. In addition to catalysis, Cu–Au nanoalloys are also of great interest in optics, in which the doping of copper into gold nanoparticles causes the appearance of strong surface plasmon resonances. In

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• additional enhancement [46]. According to the electromagnetic mechanism, on a rough surface, surface plasmon polaritons (SPPs) can also be excited by the incident light. The surface plasmons are located in the vicinity of surface defects, such as protrusions. The field enhancement at these defects leads to

Optically and electrically driven nanoantennas

• Monika Fleischer,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2020, 11, 1542–1545, doi:10.3762/bjnano.11.136

• integration, device-to-device communication, and bilateral transduction between electrons and photons [26]. An optical gap antenna typically consists of two nanostructures with a nanometer gap in between. Optical excitation induces a coupled plasmon oscillation along the two antenna parts, which can lead to

• low-background medical imaging or nanolasers [33]. Electrically driven optical antennas emit light when a bias voltage is applied to the contacted antenna arms that are forming a tunnel junction. Inelastic electron tunneling through the gap excites gap–plasmon oscillations leading to the emission of

• photons as a consequence of radiative plasmon relaxation [34][35][36]. The relaxation depends on how the gap modes couple and can hence be controlled by the design of the antenna. The combination of an electrically driven antenna with optical excitation is a very promising but not yet well explored

Superconductor–insulator transition in capacitively coupled superconducting nanowires

• Alex Latyshev,
• Andrew G. Semenov and
• Andrei D. Zaikin

Beilstein J. Nanotechnol. 2020, 11, 1402–1408, doi:10.3762/bjnano.11.124

• function at coincident points which reads where and is the velocity matrix for plasmon modes propagating along the wires. The matrix has the form where is the velocity of the Mooij–Schön modes in the ith wire in the absence of capacitive coupling between the wires, i.e. for Cm → 0. Following the

• fluctuations in one of these wires effectively decrease the superconducting properties of the other one. It follows from Equation 17 that the magnitude of such mutual influence depends on the ratio of the plasmon velocities in the two wires v1/v2 and on the strength of the capacitive coupling controlled by Cm

• . Provided the wire cross sections s1 and s2 differ strongly the plasmon velocities also differ considerably. Assume, for instance, that the first wire is much thinner than the second one. In this limit we have v1 ≪ v2 and, hence, the QPT condition (Equation 17) in the first wire remains almost unaffected

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• gold nanoparticle aggregation was implemented [54]. According to this strategy, the spherical nanoparticles, with a typical localized surface plasmon resonance (LSPR) absorption at 520 nm, aggregated in situ at the surface of the bacterial membrane. The gold nanoparticle aggregation induced a change in

Straightforward synthesis of gold nanoparticles by adding water to an engineered small dendrimer

• Sébastien Gottis,
• Régis Laurent,
• Vincent Collière and
• Anne-Marie Caminade

Beilstein J. Nanotechnol. 2020, 11, 1110–1118, doi:10.3762/bjnano.11.95

• gold nanoparticles since this color corresponds to the surface plasmon resonance wavelength. This is a well-known phenomenon observed in gold nanoparticles [56]. Considering that the gold nanoparticles are spherical, the maximum intensity of the visible spectrum at 545 nm should correspond to a mean

• size of ≈50 nm for the gold nanoparticles [57][58]. The shoulder detected at ≈630 nm corresponds to the longitudinal surface plasmon resonance, and it is characteristic of the presence of non-spherical gold NPs, in particular rod-like or triangular NPs [59][60]. The presence of this shoulder shifted

Highly sensitive detection of estradiol by a SERS sensor based on TiO₂ covered with gold nanoparticles

• Andrea Brognara,
• Ili F. Mohamad Ali Nasri,
• Beatrice R. Bricchi,
• Andrea Li Bassi,
• Caroline Gauchotte-Lindsay,
• Matteo Ghidelli and
• Nathalie Lidgi-Guigui

Beilstein J. Nanotechnol. 2020, 11, 1026–1035, doi:10.3762/bjnano.11.87

• water. SERS is mainly based on an electromagnetic effect that originates from the excitation of plasmon resonances, in particular of localized surface plasmons (LSPs) in metallic nanoparticles (NPs). Other effects may contribute to the enhancement such as the formation of hot spots or lightning rod

• µM, 100 µM, and 1 mM. Samples were left in the E2 solutions for 1 h before being rinsed with RO water and blown dry. Figure 1 gives a schematic of the final system. Optical and SERS measurements Plasmon resonance was evaluated via optical spectroscopy. For this purpose, transmission spectra were

• nm) and the Raman wavelength of the peak in consideration [5][39]. As shown in Figure 4 the plasmon resonances for all the samples were outside of this interval. The plasmonic properties of the NPs probably contribute to the enhancement of the Raman scattering. However, it also originates from the

Key for crossing the BBB with nanoparticles: the rational design

• Sonia M. Lombardo,
• Marc Schneider,
• Akif E. Türeli and
• Nazende Günday Türeli

Beilstein J. Nanotechnol. 2020, 11, 866–883, doi:10.3762/bjnano.11.72

• targeting ligands, such as angiopep-2, TAT or EGF, allows their accumulation to be increased in these specific areas [70][78][107][176]. Although to a lower extent, gold nanorods (AuNRs) have also been used for brain delivery. AuNRs, like AuNPs, exhibit an optical feature called surface plasmon resonance

• optical window. Light in this wavelength range can penetrate more deeply into the human body thanks to the low absorption by tissue and blood, making these nanoparticles interesting for theranostic treatments [177][179][180]. By excitation of surface plasmon oscillations, local heating can be generated

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

Effect of Ag loading position on the photocatalytic performance of TiO₂ nanocolumn arrays

• Jinghan Xu,
• Yanqi Liu and
• Yan Zhao

Beilstein J. Nanotechnol. 2020, 11, 717–728, doi:10.3762/bjnano.11.59

• efficiency of methylene blue (MB) compared with Ag-coated TiO2 (ACT) nanocolumn arrays and pure TiO2 nanocolumns arrays. Both experimental and theoretical simulation results demonstrated that the enhanced photocatalytic performance of AFT nanocolumn arrays was attributed to the surface plasmon resonance (SPR

• ) of Ag and the absorption of light by TiO2. These results represent a promising step forward to the development of high-performance photocatalysts for energy conversion and storage. Keywords: anodic aluminum oxide template; nanocolumn arrays; photocatalysis; surface plasmon resonance; Introduction

• surface active sites [11][12]. In addition, TiO2 combined with noble metal (e.g., Au, Ag, Pt), nanostructured to form a metal–oxide structure, has been shown to greatly improve the catalytic efficiency of the material [13]. When excited by light, noble metal nanoparticles can exhibit surface plasmon

Silver-decorated gel-shell nanobeads: physicochemical characterization and evaluation of antibacterial properties

• Marta Bartel,
• Katarzyna Markowska,
• Marcin Strawski,
• Krystyna Wolska and
• Maciej Mazur

Beilstein J. Nanotechnol. 2020, 11, 620–630, doi:10.3762/bjnano.11.49

• -resolution spectra for these elements. The direct evidence for metallic silver embedded in the polymer matrix is the spin–orbit doublet recorded at 368.3 and 374.3 eV for Ag 3d5/2 and 3d3/2, respectively (Figure 5A), followed by plasmon loss peaks at 372 and 378 eV [30][31]. However, the asymmetric shape of

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• single atom. Additionally, due to covalently bound ligands, the NCs show extraordinary stability under ambient conditions. While plasmonic AuNPs display size-dependent surface plasmon resonance (SPR), NCs display characteristic molecule-like electronic spectra. This is attributed to the small size and

• quantum confinement, and the evolution of continuous or quasicontinuous bands (of bulk gold) into discrete electronic states [40]. Another attractive property of AuNCs is photoluminescence (PL), a phenomenon that is much less understood than the surface plasmon resonance of plasmonic gold nanoparticles

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• charged silica NPs as well as the disulfide linkages between cysteine blocks and gold NPs resulted in two types of functionalities in the capsule. In a similar way, the capsules incorporated with noble metal NPs (e.g., gold and silver) respond to external light illumination by increased surface plasmon

Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions

• Robert Kozioł,
• Marcin Łapiński,
• Paweł Syty,
• Damian Koszelow,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2020, 11, 494–507, doi:10.3762/bjnano.11.40

• quality of the nanostructures, in terms of their use as plasmonic platforms, is reflected in the UV–vis absorption spectra. The absorption spectrum is dominated by a maximum in the range of 450–500 nm associated with the plasmon resonance. As the initial layer thickness increases, an additional peak

• : dewetting; finite-difference time-domain (FDTD) method; plasmon resonance; silver (Ag) nanostructures; thin films; UV–vis absorption; Introduction In the last decade there has been significant development in sensor-related research regarding the application in optical, medical or biological areas [1][2][3

• ][4][5]. The principle of some of these sensors is the resonant enhancement of a local electromagnetic field as well as a sharp spectral absorption, which can be achieved by exploiting localized surface plasmon resonance (LSPR). This phenomenon is based on collective oscillations of free electrons

Preparation and in vivo evaluation of glyco-gold nanoparticles carrying synthetic mycobacterial hexaarabinofuranoside

• Gennady L. Burygin,
• Polina I. Abronina,
• Nikita M. Podvalnyy,
• Sergey A. Staroverov,
• Leonid O. Kononov and
• Lev A. Dykman

Beilstein J. Nanotechnol. 2020, 11, 480–493, doi:10.3762/bjnano.11.39

• . Another advantage of using these GNPs is their strong light absorption due to localized surface plasmon resonance (LSPR) around 520 nm while colloids of GNPs smaller than 3 nm do not exhibit an LSPR and are barely colored. It is known that the color of GNP colloids dramatically depends on size and shape

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

• Changqiang Yu,
• Min Wen,
• Zhen Tong,
• Shuhua Li,
• Yanhong Yin,
• Xianbin Liu,
• Yesheng Li,
• Tongxiang Liang,
• Ziping Wu and
• Dionysios D. Dionysiou

Beilstein J. Nanotechnol. 2020, 11, 407–416, doi:10.3762/bjnano.11.31

• spectra were collected to study the optical properties of the samples. As shown in Figure 5a, the CuO/tourmaline composite exhibited higher optical adsorption than that of pure CuO, due to the plasmon resonance of the tourmaline units [24]. The band gap of CuO and CuO/tourmaline composite was calculated

Using gold nanoparticles to detect single-nucleotide polymorphisms: toward liquid biopsy

• María Sanromán Iglesias and
• Marek Grzelczak

Beilstein J. Nanotechnol. 2020, 11, 263–284, doi:10.3762/bjnano.11.20

• giving rise to the so-called localized surface plasmon resonance (LSPR). The position and the bandwidth of the LSPR can be modulated by the shape of the nanocrystals and can vary between 400 and 2000 nm. The high absorption cross section (plasmonic nanoparticles absorb photons over a region about ten

• times larger than their physical diameters) [59], and the lack of photobleaching (unlike organic fluorescent dyes and semiconductor nanocrystals) are additional parameters making plasmonic nanocrystals attractive materials for biosensing. Importantly, the position of the plasmon band and its bandwidth

• are also strictly related to the local environment. The collation of a nanoparticle at a nanometric distance from the surface of another nanoparticle induces a redshift of the maximum of the surface plasmon band because of plasmon coupling, causing a color change of the solution. Thus, the control

Fabrication of Ag-modified hollow titania spheres via controlled silver diffusion in Ag–TiO₂ core–shell nanostructures

• Bartosz Bartosewicz,
• Malwina Liszewska,
• Bogusław Budner,
• Marta Michalska-Domańska,
• Krzysztof Kopczyński and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2020, 11, 141–146, doi:10.3762/bjnano.11.12

• silver diffusion in Ag–TiO2 core–shell nanostructures (CSNs). Our approach comprises three simple steps starting from the synthesis of the metallic core, through its coating with titania and finally annealing leading to plasmonic hollow nanostructures with plasmon resonance in a broad spectral range. SEM

• result, to a red-shift of the plasmon resonance [20]. As can be seen from curve A in Figure 4, Ag@TiO2 CSNs have a broad absorption in the UV–vis range. This is the characteristic absorption of these composites, which does not change remarkably with a change of the shell thickness. The annealing of Ag

• @TiO2 CSNs leads to nanostructures with significantly changed optical properties as can be seen from curves B–E in Figure 4. In all cases, a red-shift of the maximum of absorption and a strengthening and widening of the plasmon resonance bands were observed. It is significant that the Ag-modified TiO2

Plasmonic nanosensor based on multiple independently tunable Fano resonances

• Lin Cheng,
• Zelong Wang,
• Xiaodong He and
• Pengfei Cao

Beilstein J. Nanotechnol. 2019, 10, 2527–2537, doi:10.3762/bjnano.10.243

• nanosensors, optical splitters, filters, optical switches, nonlinear photonic and slow-light devices. Keywords: Fano resonance; metal–dielectric–metal (MDM) waveguide; nanosensor; on-chip plasmonic structures; surface plasmon polaritons (SPPs); Introduction Surface plasmon polariton (SPP) is a unique