An atomic force microscope integrated with a helium ion microscope for correlative nanoscale characterization

• Santiago H. Andany,
• Gregor Hlawacek,
• Stefan Hummel,
• Charlène Brillard,
• Mustafa Kangül and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2020, 11, 1272–1279, doi:10.3762/bjnano.11.111

• ) and a stick–slip controller (8742-4 PicomotorTM drive, Newport Corporation). The AFM can operate in contact mode and in an off-resonance mode based on force–distance curves [24]. In this off-resonance mode, which we refer to as off-resonance tapping (ORT), the cantilever is moved sinusoidally up and

• very slow in vacuum [29]. In ORT, the tapping rate is a least one order of magnitude below the first resonance of the cantilever and hence the enhancement of the Q-factor in vacuum is less detrimental to the achievable scan speed. Results The system has been experimentally tested on a variety of sample

• surfaces in contact and off-resonance imaging modes, demonstrating the feasibility of the integration through a series of three experiments. Correlative AFM and HIM imaging is demonstrated in Figure 2 by imaging silicon nanopillars [30]. The HIM offers a large field of view, which allows for the cantilever

Magnetic-field-assisted synthesis of anisotropic iron oxide particles: Effect of pH

• Andrey V. Shibaev,
• Petr V. Shvets,
• Darya E. Kessel,
• Roman A. Kamyshinsky,
• Anton S. Orekhov,
• Sergey S. Abramchuk,
• Alexei R. Khokhlov and
• Olga E. Philippova

Beilstein J. Nanotechnol. 2020, 11, 1230–1241, doi:10.3762/bjnano.11.107

• environmental benigness [4][5][6][7][8]. These nanomaterials can be exploited in a variety of applications, including magnetic data storage [9], magnetic resonance imaging (MRI) [6][10][11][12], hyperthermia [6][13][14][15], magnetic separation [16], targeted drug delivery [6][16][17][18][19], lithium-ion

High permittivity, breakdown strength, and energy storage density of polythiophene-encapsulated BaTiO₃ nanoparticles

• Adnanullah Khan,
• Amir Habib and
• Adeel Afzal

Beilstein J. Nanotechnol. 2020, 11, 1190–1197, doi:10.3762/bjnano.11.103

• resonance absorption between two thiophene rings [17]. It demonstrates that PTh is predominantly formed by Cα–Cα conjunction during the low-temperature oxidative polymerization. The transmittance peaks at 1035 cm−1 and 788 cm−1 further prove this point as they indicate the out-of-plane bending (τCβ–H) and

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• embedded in a molecular island. The spectroscopic signatures of HOMO and LUMO are visible at, respectively, approx. −0.87 and approx. 0.92 V. The molecular resonance widths are smaller than those observed on the other surfaces; in particular, the LUMO exhibits a narrow line shape. Before analyzing the

• energy since the HOMO resonance essentially retains its energy at approx. −0.87 eV. Assuming that C42H28 is weakly coupled to the substrate, its orbital energies are expected to be aligned with the vacuum level [46] and, thus, susceptible to local changes in the work function. Site-specific work

• adjacent molecules. A finite adsorbate–substrate interaction is reflected by the presence of a molecular superstructure that matches the period of the Au(111) reconstruction. However, the HOMO resonance width has decreased by a factor of three compared to its width on Pt(111). Even vibronic progression due

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

• photothermal effect under NIR laser irradiation. Carbon nanotubes are another valuable class of nanomaterials. They have high photothermal efficiency under NIR irradiation which excites the longitudinal phonon resonance along the nanotube. The resonance peaks can be tuned by changing the tube length [86

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

• to the P=S group in the 31P nuclear magnetic resonance (NMR) spectra (Figure 1 and Table 1). Indeed, this signal shifted from 52.1 ppm in 1 to 33.7 ppm in 2 (Δδ = −18.4 ppm). The attempts to generate the gold nanoparticles from compound 2 were carried out by adding water. This compound was not very

• 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

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

• Maria Suciu,
• Corina M. Ionescu,
• Alexandra Ciorita,
• Septimiu C. Tripon,
• Dragos Nica,
• Hani Al-Salami and
• Lucian Barbu-Tudoran

Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94

• magnetic resonance imaging (MRI) (for more on this topic consult [11][12][13][14]). Among the abovementioned nanoscience products, iron oxide nanoparticles, especially superparamagnetic iron oxide nanoparticles (SPIONs) hold a lot of promise in many domains, not only regarding biology [15]. SPIONs consist

• of 2000–2019. Review Benefits of SPIONs or what makes SPIONs such a promising aspect for therapeutics and adjunct treatments Firstly, certain SPIONs are already clinically approved for magnetic resonance imaging (MRI) [24][25][26]. For this application, SPIONs have been functionalized with dextran

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• character, this choice will allow us to detect a negative ion resonance within the bandgap of MoS2. We will show that the LUMO is indeed decoupled from the metallic substrate as we can detect a narrow line width followed by a satellite structure. We can reproduce this fine structure by simulating the

• spectra on top of the molecules (Figure 4b). These show two main resonances at approx. 0.47 V and approx. 0.64 V. Another peak at approx. 1.3 V matches the Γ resonance of the bare MoS2 layer. At negative bias voltage, we observe an onset of conductance at approx. −1.8 V. The dI/dV spectra thus show that

• the STM image in Figure 4a was recorded within the energy gap of the molecule, which explains the featureless shape. In order to determine the origin of each of the resonances, we recorded constant-height dI/dV maps at their corresponding energies (Figure 5). For the first resonance at positive bias

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

• 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

• became sharper and blue-shifted, which can be attributed to the formation of Au NPs. In the annealed samples the LSP resonance (LSPR) red-shifted as a function of the Au NP size, i.e., the wavelength for maximum absorption varied from 549 nm (for the 12 Pa sample with 3 nm of Au) up to a maximum value of

Uniform Fe₃O₄/Gd₂O₃-DHCA nanocubes for dual-mode magnetic resonance imaging

• Miao Qin,
• Yueyou Peng,
• Mengjie Xu,
• Hui Yan,
• Yizhu Cheng,
• Xiumei Zhang,
• Di Huang,
• Weiyi Chen and
• Yanfeng Meng

Beilstein J. Nanotechnol. 2020, 11, 1000–1009, doi:10.3762/bjnano.11.84

• multimodal magnetic resonance imaging (MRI) technique has been extensively studied over the past few years since it offers complementary information that can increase diagnostic accuracy. Simple methods to synthesize contrast agents are necessary for the development of multimodal MRI. Herein, uniformly

• -dihydroxyhydrocinnamic acid (DHCA); dual-mode imaging; Fe3O4/Gd2O3-DHCA nanocubes; gadolinium oxide (Gd2O3); iron(II,III) oxide (Fe3O4); magnetic resonance imaging (MRI); Introduction Magnetic resonance imaging (MRI) is a noninvasive technique that has been broadly used in the clinical field to assist in disease

• until the solution was clear and transparent. After that, the solution was diluted in 10 mL of ultrapure water and finally could be used for testing. In vitro and in vivo magnetic resonance images were captured by a 3.0 T MRI scanner (MAGNETOM Skyra, Siemens Healthcare, Erlangen, Germany). The

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

• Vadim Morari,
• Aida Pantazi,
• Nicolai Curmei,
• Vitalie Postolache,
• Emil V. Rusu,
• Marius Enachescu,
• Ion M. Tiginyanu and
• Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

• about 400 meV. One can see from Figure 4 and Figure 5 that narrow emission lines related to resonance Raman scattering (RRS) are present in the emission spectrum from the ZnMgO films in addition to the broad PL bands, which is indicative of the high optical properties of the films produced by sol–gel

• spin coating. RRS from solids can be observed if the energy of the incoming or scattered photons matches real electronic states in the material. One refers to incoming and outgoing resonance, respectively [38][45][46][47]. Taking into account the band gap value and the width of band tails in ZnMgO thin

• summarized PL band maximum in Zn1−xMgxO films. The conditions of resonance Raman scattering in ZnMgO films for various compositions and temperatures. Funding The following sources of funding are acknowledged: National Agency for Research and Development of the Republic of Moldova (Grant No

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

• EGF were tested as contrast agent in an intracranial rat glioma model [30]. Functionalized SPIONs were able to cross the tumor BBB and to accumulate in the tumor and demonstrated high magnetic resonance contrast potential, confirming the ability of functionalized SPIONs to act as a diagnostic agent

Epitaxial growth and superconducting properties of thin-film PdFe/VN and VN/PdFe bilayers on MgO(001) substrates

• Wael M. Mohammed,
• Igor V. Yanilkin,
• Amir I. Gumarov,
• Airat G. Kiiamov,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2020, 11, 807–813, doi:10.3762/bjnano.11.65

• choice for superconducting MRAM materials, in which vanadium nitride (VN) serves as the superconductor. The magnetic anisotropies of a 20 nm thick Pd0.96Fe0.04 film of the first-generation epitaxial sample of VN/Pd0.96Fe0.04 on MgO(001) were studied by using a ferromagnetic resonance technique in [34

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

• ) characterization and generation using ions, electrons or other irradiation methods, the observation of ensemble paramagnetic properties and their optically detected magnetic resonance by applying a high magnetic field until the isolation of single defects and eventually their optical spin coherent control. Weber

• radiative decay process resulting in very short lifetimes. A large enhancement in spontaneous emission rate (SER) is achieved by coupling the emitter’s emission to the resonance modes of photonics/plasmonic structures. These resonator structures provide the emitter with an enhanced local density of optical

• to integrate hBN SPSs with large-scale, on-chip quantum photonic devices that work under ambient conditions or elevated temperatures. Resonant excitation of SPEs in h-BN is also used to control their quantum properties such as spectral broadening and Rabi oscillation. Using resonance excitation with

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• performed where the change in fundamental flexural resonance of the AFM probe was measured as a function of the relative piezoactuator displacement. These measurements will be referred to as Δf–d curves for the remainder of the manuscript. Δf–d curves were used to extract a relation between tip–sample

• microscopy FM-AFM is a mode of AFM that allows for the probing of tip–sample interaction forces with the possibility of atomic resolution [41]. In this method, the probe is oscillated at its fundamental flexural resonance frequency (i.e., normal to the sample) and at a constant amplitude, while it is scanned

• laterally relative to the sample. A piezoactuator acting in the z-direction brings the probe closer or further from the sample. Due to non-linear tip–sample interaction forces, the resonance frequency of the oscillating cantilever will shift. This shift can be used as a feedback signal to measure the sample

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

• resonance (SPR), which leads to strongly absorbed visible light and enhancement of local electromagnetic fields [14]. Among the noble metals, Ag nanostructures have been widely used as catalysts because of their reasonable cost and broad plasmon resonance in the visible region [15][16]. At present, the

Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach

• Edgar Cruz Valeriano,
• José Juan Gervacio Arciniega,
• Christian Iván Enriquez Flores,
• Susana Meraz Dávila,
• Joel Moreno Palmerin,
• Martín Adelaido Hernández Landaverde,
• Yuri Lizbeth Chipatecua Godoy,
• Aime Margarita Gutiérrez Peralta,
• Rafael Ramírez Bon and
• José Martín Yañez Limón

Beilstein J. Nanotechnol. 2020, 11, 703–716, doi:10.3762/bjnano.11.58

• that gives a qualitative relationship between a set of contact resonance frequencies and the indentation modulus. It is based on white-noise excitation of the tip–sample interaction and uses system theory for the extraction of the resonance modes. During conventional scanning, for each pixel, the tip

• frequency resolution, with less computational cost and at a faster speed than other similar techniques. This technique is referred to as stochastic atomic force acoustic microscopy (S-AFAM), and the frequency shifts of the free resonance frequencies of an AFM cantilever are used to determine the mechanical

• properties of a material. S-AFAM is implemented and compared with a conventional technique (resonance tracking-atomic force acoustic microscopy, RT-AFAM). A sample of a graphite film on a glass substrate is analyzed. S-AFAM can be implemented in any AFM system due to its reduced instrumentation requirements

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• signal amplitude (R) [34]. For data acquisition, we use a National Instruments card (PCI-6111) on a separate computer controlled by a LabVIEW (R2016) routine. Electric conductive commercial tips from NT-MDT, coated with W2C with a spring constant of about 3.5 N/m and a resonance frequency of about 77 kHz

• signal quality at the same time. An ac-voltage with 40 kHz and if not stated otherwise with a 2 V amplitude is overlaid over the dc-voltage during the whole measurement time. The ESM technique applied here does not use any resonance enhancement to amplify the ESM signal (such as dual resonance frequency

• tracking (DRFT or DART) or band excitation (BE)), but uses a single tracking frequency, as it was already performed by Luchkin et al. [30]. Using a single tracking frequency far off the resonance frequency range of the tip–sample system limits the measurable signal intensity, but avoids any measurement

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

• allowed for plasmonic and magnetic resonance, and luminescence in a single composite system for plasmonic photothermal therapy (PPTT). The bioimaging capability of the plasmonic magneto-luminescent multifunctional nanocarrier (PML-MF) systems were studied in vitro using three types of cancer cells, namely

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

• resonance of the outer shell electrons present in noble metals. The absorbed light is converted to heat energy, which causes layer damage, thereby opening the capsules and releasing the encapsulated material [83]. The parameters such as the preparation condition of capsules, the distribution and aggregation

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

• appears around 350 nm, which probably corresponds to the quadrupole resonance. For calculations leading to a better illustration of absorption, scattering and overall absorption of light in Ag nanoparticles, the Mie theory is employed. Absorbance and the distribution of the electromagnetic field around

• : 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

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

Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis

• Berkin Uluutku and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37

• of the force pulses the probe jumped from contact point to contact point rather than exhibiting a constant, nearly resonant intermittent-contact oscillation (the oscillation frequencies used were much smaller than the resonance frequency of the cantilever). In this paper, we propose the use of

Atomic-resolution imaging of rutile TiO₂(110)-(1 × 2) reconstructed surface by non-contact atomic force microscopy

• Daiki Katsube,
• Shoki Ojima,
• Eiichi Inami and
• Masayuki Abe

Beilstein J. Nanotechnol. 2020, 11, 443–449, doi:10.3762/bjnano.11.35

• 10 pA, respectively. (a) STM and (b) NC-AFM images of a rutile TiO2(110)-(1 × 2) reconstructed surface. (c, d) Height profiles along black (STM) and blue (NC-AFM) lines in the images. The STM and NC-AFM images were obtained using a Pt-coated Si cantilever with a resonance frequency of f0 = 154.1 kHz

• cantilever with a resonance frequency of f0 = 154.1 kHz and a spring constant of k = 27.05 N/m. The measurement parameters were Δf = −38.1 Hz, A = 9.8 nm, and Vs = 350 mV. The asymmetric Ti2O3 model is included with the height profile in (d) for comparison of the surface geometry and the model. Area

• a resonance frequency of f0 = 154.9 kHz and a spring constant of k = 27.05 N/m. The measurement parameters were A = 10.9 nm, and Vs = 850 mV. The green and yellow regions in (b) indicate Ti2O3 rows with the left side and the right side in higher positions, respectively. Funding This work was

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

• of the samples were mixed with 2 mL of ethanol followed by 10 min of sonication. Then, 50 µL of 5% Nafion were added, and the obtained mixture was magnetically stirred for 24 h. Finally, the mixture was coated on ITO glass and dried in a vacuum oven for 12 h. Electron paramagnetic resonance (EPR

• 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