Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• . The vibration modes of a qPlus sensor with a long tip are quite different from those of a cantilever with a short tip. Flexural vibration of the tungsten tip will occur. The tip can no longer be considered as a rigid body that moves with the prong of the tuning fork. Instead, it oscillates both

• horizontally and vertically. The vibration characteristics of qPlus sensors with different tip sizes were studied. An optimized tip size was derived from obtained values of tip amplitude, ratio between vertical and lateral amplitude components, output current, and quality factor. For high spatial resolution

• can be detected due to the multi-directional vibration of the tip [17]. Furthermore, by using a qPlus sensor with a long tilted tip, vertical incident light can be coupled to the tip apex. This setup has the added benefit of locating the exact target location with high resolution when it is combined

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• , which is expected due to the quantum confinement effect [13]. Another crucially important optical characterization technique for the investigation of defects is Raman spectroscopy. The phonon vibration modes are highly sensitive to the existence of point defects, which are reflected in distinct spectral

• mode, which is indicative of a large amount of defect centers. The existence of defect centers affects the vibration mode and eventually causes a blueshift, as shown in Figure 1d. Finally, the electrical properties obtained via CV and EIS can also be correlated with the defect structures when the

• structures with a hexagonal crystal lattice. Because the aluminum was removed, there is no visible Raman vibration. Moreover, CV, chronopotentiometry (CP), and EIS were used to test the electrochemical behavior of the synthesized tantalum carbide MXenes. In 0.1 M sulfuric acid (H2SO4) as electrolyte, a

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

• describing the vibration of a cantilever of length L in free space [16][27]: The first two roots of Equation 3 are = 1.8751 and = 4.6941 [28]. Equation 1 has two important features affecting the feasibility of CR measurements. First, it can be used only to calculate the normalized contact stiffness α as a

• measurements. In different series of measurements, the static force exerted on the sample by the tip has been varied. A sufficiently small excitation amplitude has been chosen for the frequency sweep, so that the vibration amplitude is always smaller than the static indentation of the sample and the tip always

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

• vibration and silver material is expelled from the target surface in the form of a plasma plum. Thus, silver ions Ag+ and sulfur ions S2− are produced from silver target and thiourea solution, respectively. They form Ag2S NPs according to the following chemical reaction [21]: Figure 3 shows the XRD patterns

• reported data [24]. Figure 4 shows the Raman spectra of Ag2S NPs synthesized in Tu solution with and without CTAB. Four vibration modes were assigned to Ag2S. The peaks at 45 and 65 cm−1 are related to Ag–S bonds (Ag modes) [25]. The third peak at 480 cm−1 was indexed to the longitudinal optical phonon 2LO

• the range of 500–4000 cm−1 are shown in Figure 7. The peaks at 541, 640, and 2210 cm−1 were indexed to the characteristic vibration of the Ag–S bond. The peak at 1460 cm−1 can be indexed to C–C stretching vibration, and the peak at 1650 cm−1 belonged to the stretching vibration of the sulfide group

Walking energy harvesting and self-powered tracking system based on triboelectric nanogenerators

• Mingliang Yao,
• Guangzhong Xie,
• Qichen Gong and
• Yuanjie Su

Beilstein J. Nanotechnol. 2020, 11, 1590–1595, doi:10.3762/bjnano.11.141

• . Recently, triboelectric nanogenerators (TENGs) have been invented, which offer an innovative combination between electrostatic induction and contact electrification. These devices are able to harvest mechanical energy from a vast array of sources, such as body motion [16][17][18][19], vibration [20][21][22

Design of V-shaped cantilevers for enhanced multifrequency AFM measurements

• Mehrnoosh Damircheli and
• Babak Eslami

Beilstein J. Nanotechnol. 2020, 11, 1525–1541, doi:10.3762/bjnano.11.135

• introduced other models to calculate spring constants [22][23]. These methods were improved by Sader to a higher accuracy [11][24]. As a second category of application of V-shaped cantilevers, dynamic AFM is used to characterize soft matter. For example, Korayem et al. have carried out a free-vibration

• vibrational behavior of rectangular and V-shaped AFM cantilevers using FEM [27]. All abovementioned researchers focused on the accuracy and sensitivity of the microscope by interpreting and analyzing the dynamic and vibration behavior. One way to increase accuracy and sensitivity in atomic force microscopy is

• exciting the higher modes of the cantilever (higher-modes AFM) or exciting multiple modes simultaneously (multifrequency AFM). It is important to simulate the dynamic and vibration behavior of the AFM under these conditions to interpret the dependency of sensitivity and material composition contrast on

Structural and electronic properties of SnO₂ doped with non-metal elements

• Jianyuan Yu,
• Yingeng Wang,
• Yan Huang,
• Xiuwen Wang,
• Jing Guo,
• Jingkai Yang and
• Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

• characteristic frequency of the material. The plasma oscillation frequencies vary for different crystal materials. In general, it is proportional to the concentration of free electrons. When the vibration frequency of the incident light is greater than the plasma oscillation frequency, the crystal material is

Structure and electrochemical performance of electrospun-ordered porous carbon/graphene composite nanofibers

• Yi Wang,
• Yanhua Song,
• Chengwei Ye and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 1280–1290, doi:10.3762/bjnano.11.112

• stirred at room temperature for 2 h until a homogeneous solution was obtained. Then 0.5 wt % of graphene was added to the PAN/DMF solution, which was submitted to ultrasonic vibration for 30 min until graphene was well-dispersed in the solution. Finally, DIW was added to the graphene/PAN/DMF solution upon

• , 1378 and 1452 cm−1 were due to the bending of the C−H of PAN, the absorption peak at the wavelength of 2243 cm−1 was attributed to the stretching vibration of C−N, and the absorption peak at 1668 cm−1 was generated by the stretching vibration of C=C [35]. As shown in Figure 3a, upon addition of

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

• vibration (νTi–O) of BTO structure [13][14]. PTh is characterized by the symmetric and asymmetric stretching vibrations (νC=C) of the aromatic ring at 1628 and 1385 cm−1, a sharp aromatic ring deformation (δC–S–C) at 610 cm−1, and a typical stretching vibration of the aromatic β-hydrogens (νCβ–H) at 3060 cm

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

• the hole or electron to the vibrational quantum with energy hν. The Huang–Rhys factor can be expressed as where εν denotes the relaxation energy of the vibration when charging the molecule [10][41]. Comparing the peak height of the orbital signature (I0) with the first vibronic subband (Iν,1) enables

• previously determined on a theoretical basis to exhibit a particularly strong Holstein coupling to the HOMO of C42H28 embedded in a molecular crystal [42]. Generally speaking, the Holstein coupling describes the local interaction of a charge carrier with a molecular vibration [40] and may therefore be

• ) and corresponds to the vibrational mode with large Holstein coupling (vide supra). The second vibrational quantum with energy hν2 ≈ 220 meV is likely to coincide with the C42H28 vibration with energy 1594 cm−1 ≈ 200 meV, which was likewise predicted to exhibit an elevated Holstein coupling [42]. The

Vibration analysis and pull-in instability behavior in a multiwalled piezoelectric nanosensor with fluid flow conveyance

• Sayyid H. Hashemi Kachapi

Beilstein J. Nanotechnol. 2020, 11, 1072–1081, doi:10.3762/bjnano.11.92

• , pharmaceutical, agricultural, environmental, advanced materials, chemical science, physics, electronics, information technology, biomedical and medical fields [1][2][3][4][5][6][7][8][9][10]. Due to this extended use of nanosensors, especially piezoelectric nanosensors in vibration devices, mathematical models

• and the study of vibration behavior are essential. Additionally, it is important that the size-dependent parameters for the dynamics analysis and mathematical modeling of these nanostructures be contained in the theoretical models. For this reason, surface/interface elasticity, which was addressed by

• result, MWNS materials are preferred in many applications such as nanoresonators. Many studies have been carried out on the vibration and stability analysis of nanostructures with some reviews given as follows. Strozzi and Pellicano investigated the vibration analysis of triple-walled carbon nanotubes

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

• group, where no nodal planes exist in the LUMO, as their presence may lead to vibration-assisted tunneling in addition to the bare Franck–Condon excitation [52]. Conclusion We have shown that a single layer of MoS2 may act as a decoupling layer for molecules from the underlying metal surface, if the

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

• Raman spectra of the powder can be observed, which are due to the fact that the molecule is bound to the aptamer, affecting the vibration frequencies. For instance, the peak at 743 cm−1 corresponds to the peak at 730 cm−1 in the E2 Raman spectra, while the peak at 822 cm−1 corresponds to the peak at 830

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

• absorption peaks. On the one hand, the FGOA nanocubes have characteristic absorption peaks at 2937 and 2857 cm−1, corresponding to the stretching vibration of –CH3 and –CH2, respectively, which are both present in oleic acid. On the other hand, the FGDA nanocubes have the characteristic absorption peak at

• 1617 cm−1, corresponding to the benzene ring stretching vibration, which indicates that DHCA successfully modified the FGDA nanocubes. In order to verify the magnetic properties of FGDA nanocubes, the field-dependent magnetization (M–H) curves (Figure 2j) were obtained from the physical property

A 3D-polyphenylalanine network inside porous alumina: Synthesis and characterization of an inorganic–organic composite membrane

• Jonathan Stott and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2020, 11, 938–951, doi:10.3762/bjnano.11.78

• , respectively [64]. Whereas the amide A mode is assigned to an intermolecular hydrogen-bonded NH stretching vibration, the amide B band is due to the "free" NH stretching vibration and amide II to the NH bending motion of the peptide bond. Schultz et al. demonstrated a correlation between the amide I band (C=O

• stretching vibration) at 1641 cm−1 (indicating a β-sheet conformation) in the MIR region and the combination band of amide A and amide II in the NIR region at 4867 cm−1 [68]. The authors observed an increase of intensity as well a small red shift of the combination band between 4890 and 4860 cm−1 with

• −1 of the polyphenylalanine functionalized membrane from pure DCM. MIR spectra of polyphenylalanine synthesized from solution (pure THF black line and pure DCM red line) at different wavenumber regions. Dotted lines indicate typical values of the amide I vibration band for α-helix (around 1665 cm−1

Light–matter interactions in two-dimensional layered WSe₂ for gauging evolution of phonon dynamics

• Avra S. Bandyopadhyay,
• Chandan Biswas and
• Anupama B. Kaul

Beilstein J. Nanotechnol. 2020, 11, 782–797, doi:10.3762/bjnano.11.63

• which was originally formulated for diamond [55], and is also applicable here, as given by Equation 7 below, where ω0 is the frequency of vibration of the and A1g modes at T = 0 K and χT is the first-order Raman temperature coefficient calculated for both the and A1g modes (just as in the computation

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

• and clarified their temperature dependence of the ZPL peak shift, line width, and PL intensity ranging from 4 to 300 K. The temperature-dependent line width, spectral energy shift, and intensity differing ZPLs are described by a lattice vibration model that considers piezoelectric coupling to in-plane

Preparation, characterization and photocatalytic performance of heterostructured CuO–ZnO-loaded composite nanofiber membranes

• Wei Fang,
• Liang Yu and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 631–650, doi:10.3762/bjnano.11.50

• studies. FTIR and XRD analysis: FTIR was used to characterize the CNFMs with different [Cu(Ac)2/Zn(Ac)2]/[PVDF/PAN] weight ratios (Figure 7). The peaks at 879 cm−1 correspond to the asymmetric stretching vibration of –CF2– in PVDF. The peaks at 1070 and 1276 cm−1 represent the β-phase of PVDF. There was

• also an obscure peak near 1070 cm−1, which might belong to –C–C– stretching vibrations. The peak at 2250 cm−1 corresponds to the stretching vibration of –CN– in PAN and the peak at 2942 cm−1 can be assigned to the stretching vibration of –CH2–. The spectra of the CNFMs with Cu(Ac)2 and Zn(Ac)2 (Figure

•  7b–e) have a wide peak at 1573 cm−1, which represents the antisymmetric stretching vibration of –COO–, indicating that these CNFMs include Cu(Ac)2 and Zn(Ac)2 [38][39][40]. The change of the [Cu(Ac)2/Zn(Ac)2]/[PVDF/PAN] weight ratio has little influence on the spectra. In order to determine the

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

• is characteristic of C–H out-of-plane vibrations in para-substituted benzene rings. On the other hand, the 756 cm−1 mode is attributable to monosubstituted benzene due to the out-of-plane bending vibration of the five CH groups in the aromatic ring. The presence of these two bands confirms therefore

Soybean-derived blue photoluminescent carbon dots

• Shanshan Wang,
• Wei Sun,
• Dong-sheng Yang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2020, 11, 606–619, doi:10.3762/bjnano.11.48

• %, suggesting the presence of similar chemical-bonding structures. For example, both CDs possess the bonds of O–H and N–H stretching vibration at 3344 cm−1 and 3366 cm−1 [43][44], respectively. The presence of the O–H and N–H groups makes the CDs hydrophilic and improves the stability and dispersibility of the

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

• , which is induced by the ionic vibration in the material. Due to the modified experimental set-up, the presented ESM technique does not correspond to the classical ESM technique introduced by Balke et al. [24], but is similar to the time-domain measurements reported by Jesse et al. [33], therefore we

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

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• presence of the azo compounds was verified using a combination of Fourier-transform infrared (FTIR) and UV–vis absorption spectroscopy. A characteristic vibration at 2991 cm−1, which can be associated to the N–H stretching vibrations of the ammonium headgroup (Figure 4E), vanishes completely for 3D-AzoC2

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

• molecular vibration characterization revealed that CuO chemically interacted with tourmaline via Si–O–Cu bonds. The specific surface area of the CuO/tourmaline composite (23.60 m2 g−1) was larger than that of the pristine CuO sample (3.41 m2 g−1). The CuO/tourmaline composite exhibited excellent

• spectroscopy. As shown in Figure 2, three bands appeared at 3487 cm−1, 3554 cm−1, and 3635 cm−1 resulting from the vibration of the three OH groups in tourmaline [2]. The bending vibration of the Si–O group was detected at 488 cm−1 [27]. The band at 649 cm−1 was due to the RIV–O (R = Al, Fe, Mg, Mn) stretching

• vibration, and the peaks at 708 cm−1 and 777 cm−1 result from the Si–O–Si stretching vibration [2][28]. A well-resolved band at 974 cm−1 originated from the Si–O stretching vibration [29], and was shifted to 989 cm−1 with a blue-shift of 15 cm−1 for the CuO/tourmaline composite compared with that of the

Poly(1-vinylimidazole) polyplexes as novel therapeutic gene carriers for lung cancer therapy

• Gayathri Kandasamy,
• Elena N. Danilovtseva,
• Vadim V. Annenkov and
• Uma Maheswari Krishnan

Beilstein J. Nanotechnol. 2020, 11, 354–369, doi:10.3762/bjnano.11.26

• investigated by using FTIR and DSC (Figure 2). The FTIR of PVI shows vibration bands at 2950 cm−1 (imidazole C–H stretching vibrations) and at 1645, 1506 and 1411 cm−1 (imidazole C–N stretching vibrations). The N–H in-plane bending vibrations are observed at 1235 cm−1. The polyplex also shows stretching