The preparation temperature influences the physicochemical nature and activity of nanoceria

• Robert A. Yokel,
• Wendel Wohlleben,
• Johannes Georg Keller,
• Matthew L. Hancock,
• Jason M. Unrine,
• D. Allan Butterfield and
• Eric A. Grulke

Beilstein J. Nanotechnol. 2021, 12, 525–540, doi:10.3762/bjnano.12.43

• hydrodynamic diameter (Smoluchowski's approximation) of the as-prepared- (as-loaded) and the partially dissolved nanoceria was determined by dynamic light scattering (DLS) using a Brookhaven 90Plus Particle Size Analyzer. The zeta potential (0.5 mg/mL) from pH 0.5 to 13, adjusted with nitric acid and sodium

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

• Raman scattering (SERS) effect. In this work, we show the SERS effect for water molecules in the dispersion of silver nanoparticles (AgNPs) without any external electrical field. An enhancement factor was estimated to be (4.8 ± 0.8) × 106 for an excitation wavelength of 514.5 nm and for AgNPs with an

• ; plasmons; resonance Raman effect; surface-enhanced Raman scattering; water structure; Introduction What is the structure of water? This question is among the 125 most important unanswered questions of mankind and it was proposed by the prestigious Science Magazine [1]. Water is the most common compound in

• effect weaker [20]. Silver nanoparticles (AgNPs) are gaining more and more popularity in various applications, such as electronics [22], photonics [23], and medicine [24]. Silver nanocolloids are also commonly used as an enhancing substrate in surface-enhanced Raman scattering (SERS) [25][26]. Since the

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

• , especially those with anisotropic structure, such as AuNRs, Au nanocages [5][6], Au nanostars [7][8], Au nanospheres [9][10], and Au nanoshells [11][12], show great potential as PTAs. Particularly, AuNRs, with a high inherent absorption–scattering ratio, simple and controllable synthesis, and high PCE [13

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

• induce the production of hot electrons from plasmonic metals, while larger size nanoparticles favor the scattering of the light. There is a strong electromagnetic field that is produced by fast and coherent oscillating electrons which extend into the metal and the surrounding environment [62][63]. The

• excite the plasmons (Mie scattering theory). For example, the main absorption wavelength (dipole) of spherical AgNPs (10 nm of size) is at ≈400 nm. Larger AgNPs and AgNPs with different shapes, on the other hand, absorb different light wavelengths due to other absorption modes, generally higher than 400

• , UV–vis spectroscopy, inductively coupled plasma optical emission spectrometry (ICP-OES), dynamic light scattering (DLS), among other techniques [33]. The basic principles of the techniques mentioned here are detailed in the following sections. Each AgNPs is unique, depending on its size, state of

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

• -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

• modulation setup. The spatial displacement of the focus modulates the signal [61] and the lock-in coupled detector provides an excellent signal-to-noise ratio for individual small scatterers. Figure 7d–f shows the extinction (sum of scattering and absorption) spectra corresponding to the tetramers in Figure

• round. Each monomer acts as a small dipole in our measurement configuration and its response is not very sensitive to its actual shape as long as surface roughness does not increase the scattering losses. Finite-difference time-domain modeling taking into account the slightly varying geometries led to

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

• properties such as significant absorption or scattering in the visible and near-infrared (NIR) regions, tunable aspect ratio, biocompatibility, fluorescence properties, and the ease of biofunctionalization, which makes them ideal in biomedical applications [13]. Gold-based nanomaterials (i.e., nanospheres

Characterization, bio-uptake and toxicity of polymer-coated silver nanoparticles and their interaction with human peripheral blood mononuclear cells

• Sahar Pourhoseini,
• Reilly T. Enos,
• Angela E. Murphy,
• Bo Cai and
• Jamie R. Lead

Beilstein J. Nanotechnol. 2021, 12, 282–294, doi:10.3762/bjnano.12.23

• pristine AgNPs, including dynamic light scattering (DLS), UV–vis spectroscopy (UV–vis), transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometry (ICP-MS). DLS gave a Z-average hydrodynamic size of 33.7 ± 0.7 nm (mean ± standard deviation) and a PDI (polydispersity index) of

Differences in surface chemistry of iron oxide nanoparticles result in different routes of internalization

• Barbora Svitkova,
• Vlasta Zavisova,
• Veronika Nemethova,
• Martina Koneracka,
• Miroslava Kretova,
• Filip Razga,
• Monika Ursinyova and
• Alena Gabelova

Beilstein J. Nanotechnol. 2021, 12, 270–281, doi:10.3762/bjnano.12.22

• characteristics of these nanoparticles in the solvent and culture medium are shown in Table 1. Dynamic light scattering (DLS) Particle size distribution and zeta potential of the surface-modified MNPs in stock solution and culture medium were determined by DLS using a Zetasizer Nano-ZS (Malvern Instruments, UK

Gold(I) N-heterocyclic carbene precursors for focused electron beam-induced deposition

• Cristiano Glessi,
• Aya Mahgoub,
• Cornelis W. Hagen and
• Mats Tilset

Beilstein J. Nanotechnol. 2021, 12, 257–269, doi:10.3762/bjnano.12.21

• between precursors, probably reflecting the difference in composition, which influences the electron scattering in the pillars. Conclusion Seven gold NHC complexes of the form (Y,R)AuX were synthesized and thermally characterized. The sublimation temperature Ts of the compounds was observed to decrease

Scanning transmission helium ion microscopy on carbon nanomembranes

• Daniel Emmrich,
• Annalena Wolff,
• Nikolaus Meyerbröker,
• Jörg K. N. Lindner,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 222–231, doi:10.3762/bjnano.12.18

• detector in the dark field [20]. Kavanagh et al. used a silicon diode array as a pixelated sensor for transmission imaging to observe ion beam scattering with a static beam and as an end-point detection for pore milling into graphite sheets [21]. This work presents the design and capabilities of a dark

• –Thornley detector (ETD). Ions that are transmitted through a thin specimen (e.g., a membrane), undergo elastic and inelastic scattering processes, which lead to deflection of the ion trajectories. Depending on the resulting scattering angle, the transmitted ions hit different points on the conversion plate

• a signal that can be detected with the ETD. Therefore, the brightness of a pixel in the final image is determined by the degree of scattering. Additionally, the brightness is determined by the acceptance angle α of the STIM holder. This angle is defined by the size of the hole on the conversion

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

• resonance (SPR) and generally have a broad absorption spectrum [83]. This enables applications in optoelectronics and surface-enhanced Raman scattering [84][85]. AgNPs were also applied effectively in solar cell matrices [32][86][87]. AgNPs can enhance the current density in solar cells due to their far

Effect of different silica coatings on the toxicity of upconversion nanoparticles on RAW 264.7 macrophage cells

• Cynthia Kembuan,
• Helena Oliveira and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 35–48, doi:10.3762/bjnano.12.3

• -aminopropyltrimethoxysilane (AHAPS), which provides the nanoparticle surface with a positive charge, increasing their interaction with the cell membrane. The particles were characterized by scanning transmission electron microscopy (STEM), dynamic light scattering (DLS), electrophoretic light scattering (ELS), and

• present study. The sample UC@thin_NH2 has a larger hydrodynamic diameter than the sample UC@thick_NH2 in DMEM and the situation is reversed for sample UC@thin_RBITC_NH2 and sample UC@thick_RBITC_NH2. However, in both cases the cell viability increases with shell thickness. Since the light scattering is

• or particles adsorbed onto cellular membranes, relying on the fact that when cells internalize nanoparticles they increase their internal complexity [66][67]. Several publications have shown that side-scattering correlates with the concentration of nanoparticles attached to or taken up by cells [67

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

• ). Ion collisions with a nucleus in the sample result in (back-)scattering of the primary ion, displacement of atoms in the sample, sputtering of material and generation of phonons (heat). However, incoming ions also undergo many interactions with electrons in the sample, leading to the generation of

• detectors Rutherford back-scattering (RBS) of high-energy (typically in the range of 1 to 5 MeV) ions is a well-known (micro)analytical technique for the investigation of the elemental composition of a sample. Recently, Klingner, Heller, and Hlawacek demonstrated a time-of-flight RBS spectrometer for the

• HIM [32][34][49]. We are not aware of any currently published biological application of RBS in the HIM. However, from scattering kinetics it follows that RBS is most sensitive to heavy elements in a light matrix. For bio-imaging this implies that RBS could be a promising technique to study systems

Scanning transmission imaging in the helium ion microscope using a microchannel plate with a delay line detector

• Eduardo Serralta,
• Nico Klingner,
• Olivier De Castro,
• Michael Mousley,
• Santhana Eswara,
• Serge Duarte Pinto,
• Tom Wirtz and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2020, 11, 1854–1864, doi:10.3762/bjnano.11.167

• the sample with the position (scattering angle) and time of the transmission events. Various imaging modes, such as bright field and dark field or the direct image of the transmitted signal, can be created by post-processing the collected STIM data. Furthermore, the detector has high spatial and

• high-angle scattering events, or moving it down to increase the angular resolution and distance for time-of-flight measurements. With this new system, we show composition-dependent contrast for amorphous materials and the contrast difference between small-angle and high-angle scattering signals. We

• using the beam deflected in a polar and azimuthal angular sector. For amorphous materials under perpendicular incidence, the transmitted beam is expected to be scattered symmetrically around the axis of incidence. The average polar angle of scattering depends on both the material and the thickness of

Piezotronic effect in AlGaN/AlN/GaN heterojunction nanowires used as a flexible strain sensor

• Jianqi Dong,
• Liang Chen,
• Yuqing Yang and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1847–1853, doi:10.3762/bjnano.11.166

• introduced during the epitaxial growth process [1][2][3]. Furthermore, the analysis of the internal polarization of the AlGaN/AlN/GaN heterojunction showed the existence of a 2D electron gas (2DEG), which effectively suppresses the degradation of the carrier mobility caused by the scattering at charge

Unravelling the interfacial interaction in mesoporous SiO₂@nickel phyllosilicate/TiO₂ core–shell nanostructures for photocatalytic activity

• Bridget K. Mutuma,
• Xiluva Mathebula,
• Isaac Nongwe,
• Bonakele P. Mtolo,
• Boitumelo J. Matsoso,
• Rudolph Erasmus,
• Zikhona Tetana and
• Neil J. Coville

Beilstein J. Nanotechnol. 2020, 11, 1834–1846, doi:10.3762/bjnano.11.165

• ]: where F(R) is the Kubelka–Munk function, α is the absorption coefficient and S is the scattering coefficient (n = 2 or 0.5 for direct or indirect transitions, respectively). The functional groups on mSiO2@NiPS and mSiO2@NiPS/TiO2 composites were determined using a Bruker Tensor 27 Fourier-transform

PEG/PEI-functionalized single-walled carbon nanotubes as delivery carriers for doxorubicin: synthesis, characterization, and in vitro evaluation

• Shuoye Yang,
• Zhenwei Wang,
• Yahong Ping,
• Yuying Miao,
• Yongmei Xiao,
• Lingbo Qu,
• Lu Zhang,
• Yuansen Hu and
• Jinshui Wang

Beilstein J. Nanotechnol. 2020, 11, 1728–1741, doi:10.3762/bjnano.11.155

• -COOH sample is distinctly smaller than that of the raw SWCNTs, and the sample treated with H2SO4/HNO3 mixed acid solution has the most even size distribution. The particle size of CNTs modified by PEG and PEI increases slightly. It should be noted that dynamic light scattering (DLS) is mainly suitable

Application of contact-resonance AFM methods to polymer samples

• Sebastian Friedrich and
• Brunero Cappella

Beilstein J. Nanotechnol. 2020, 11, 1714–1727, doi:10.3762/bjnano.11.154

• –distance curves enable the clear distinction of six different thickness values between a 45 nm thick film and bulk PMMA, whereas data scattering and the small differences between the frequencies (≅4 kHz) would hardly allow one to discern a further curve in Figure 7 between those corresponding to the 45 nm

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

• satellites around the specular spot caused by multiple electron scattering as reported in [30]. PTCDA was evaporated from a glass crucible. The molecular flux was also monitored by the QMS at m/z 392, which corresponds to the mass of the non-fractured PTCDA molecule. The flux was typically one monolayer per

• shift of 1,310 cm−1. This is higher in energy by 13 cm−1 compared to the Raman shift (1,297 cm−1) for the RB mode of a layer at room temperature (RT) [42]. The special role of this RB mode will be discussed in further detail below. 2.1 Surface-enhanced Raman scattering The fact that the Raman modes of a

• small quantity of molecules can be observed here at all is attributed to surface-enhanced Raman scattering (SERS) [45]. This effect is most commonly observed on rough surfaces of noble metals [45] or at metal nanostructures [46], and it is utilized in surface-enhanced Raman spectroscopy [47]. There are

Selective detection of complex gas mixtures using point contacts: concept, method and tools

• Alexander P. Pospelov,
• Victor I. Belan,
• Dmytro O. Harbuz,
• Volodymyr L. Vakula,
• Lyudmila V. Kamarchuk,
• Yuliya V. Volkova and
• Gennadii V. Kamarchuk

Beilstein J. Nanotechnol. 2020, 11, 1631–1643, doi:10.3762/bjnano.11.146

• generation and nonlinear electric current processes in the contact caused by scattering of electrons in a nonequilibrium state are spatially separated [30]. The separation of nonlinear electric current phenomena from other interactions allows us to directly observe their energy component as a result of the

• conductance result only from scattering processes of electrons in a nonequilibrium state [30]. In addition, the voltage sweep in the contact ranges widely and so does the excess energy of nonequilibrium electrons, which they can transfer as a result of the interaction. This allows us to effectively influence

• molecule, the molecule can be characterized by a certain energy of interaction with the gas-sensing matrix material (i.e., the adsorption energy). Any adsorption event in the Yanson point contact entails a redistribution of the electron density in the conduction channel of the point contact, the scattering

High-responsivity hybrid α-Ag₂S/Si photodetector prepared by pulsed laser ablation in liquid

• Raid A. Ismail,
• Hanan A. Rawdhan and
• Duha S. Ahmed

Beilstein J. Nanotechnol. 2020, 11, 1596–1607, doi:10.3762/bjnano.11.142

• intensity of peaks (surface-enhanced Raman scattering) due to the reduced agglomeration and aggregation of particles and the small size of the Ag2S particles prepared under the effect of the CTAB surfactant [29]. Inset of Figure 4 is the Raman spectrum of thiourea solution, in which three peaks were

• of the nanoparticles was decreased after adding CTAB, which results in decreasing optical absorption. The agglomerated NPs can be considered as scattering centers in solution, and hence the optical absorption of Ag2S increased [30]. A small absorption peak was detected at 355 nm for Ag2S prepared

Fabrication of nano/microstructures for SERS substrates using an electrochemical method

• Jingran Zhang,
• Tianqi Jia,
• Xiaoping Li,
• Junjie Yang,
• Zhengkai Li,
• Guangfeng Shi,
• Xinming Zhang and
• Zuobin Wang

Beilstein J. Nanotechnol. 2020, 11, 1568–1576, doi:10.3762/bjnano.11.139

• electrochemical method, three-dimensional arrayed nanopore structures are machined onto a Mg surface. The structured Mg surface is coated with a thin gold (Au) film, which is used as a surface-enhanced Raman scattering (SERS) substrate. A rhodamine 6G (R6G) probe molecule is used as the detection agent for the

Electrokinetic characterization of synthetic protein nanoparticles

• Daniel F. Quevedo,
• Cody J. Lentz,
• Adriana Coll de Peña,
• Yazmin Hernandez,
• Nahal Habibi,
• Rikako Miki,
• Joerg Lahann and
• Blanca H. Lapizco-Encinas

Beilstein J. Nanotechnol. 2020, 11, 1556–1567, doi:10.3762/bjnano.11.138

• diameter of 299 ± 128 nm (Figure 1b). The particles were subsequently collected and suspended in media. After allowing the particles to equilibrate for 24 h, the average particle diameter value increased to 356 ± 190 nm according to dynamic light scattering (DLS) measurements. The size distribution curves

• hydrodynamic diameter values of 373 ± 180 nm and 356 ± 190 nm, respectively (Figure 2a). The zeta potential values (ζp) of the SPNPs were also measured via electrophoretic light scattering in the same suspension medium used in the EK experiments. The obtained results were −20.0 ± 0.6 mV for the SPNP-BSA-488

• the desired particles. Particles, in their dry state, were imaged using SEM for shape analysis. To determine their hydrodynamic size distribution after being hydrated, the particles were suspended in ultrapure H2O + 0.01% Tween 20, sonicated on ice, and measured with dynamic light scattering (Malvern

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

• . Prominent examples are SERS and TERS, where the intrinsically small Raman scattering cross-section is enhanced by several orders of magnitude, making single-molecule spectroscopy feasible. These spectroscopic techniques have shown tremendous progress in the last two decades [29][30][31][32]. Under high

• sizeable third-harmonic generation from the pillar. The fact that nonlinear effects can already be observed in the absorption and scattering of single gold nanoparticles at much lower laser intensities is demonstrated in [56]. Using the so-called x-scan technique, a nanoparticle is scanned through a

Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir

• Mathias Franz,
• Romy Junghans,
• Paul Schmitt,
• Adriana Szeghalmi and
• Stefan E. Schulz

Beilstein J. Nanotechnol. 2020, 11, 1439–1449, doi:10.3762/bjnano.11.128

• analysed by Fazio et al. [1]. It is mainly based on multiple light scattering at the silicon nanowires. Figure 4 shows SEM images of an etched wafer using Au nanoparticles as etching catalyst. This wafer has been etched with 50 mmol/L H2O2 for 10 min. The SEM images show cross sections of the wafer centre

• significantly on the wafers. The process is quite homogeneous over the whole wafer. The straight etching profile indicates that the main etching occurred in the first etching regime (where n = 4). The top-view SEM image in Figure 4e has been acquired with increased electron energy. Using a back-scattering

• is caused by multiple light scattering and reflection within the nanostructures [1]. The wafers etched with a higher H2O2 concentration show a lower mean reflectance. This lower reflectance is correlated to the increased etching depth with increasing H2O2 concentration. All these wafers contain