Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• magnetoelectric core–shell composite nanowires had a magnetostrictive core and a piezoelectric shell, and it exhibited a strain-mediated magnetoelectric effect. In terms of device design and manufacturing, this biphasic core–shell configuration offered greater flexibility than single-phase magnetoelectric

Nanogenerator-based self-powered sensors for data collection

• Yicheng Shao,
• Maoliang Shen,
• Yuankai Zhou,
• Xin Cui,
• Lijie Li and
• Yan Zhang

Beilstein J. Nanotechnol. 2021, 12, 680–693, doi:10.3762/bjnano.12.54

• rehabilitation, sports training, human motion recognition, respiratory monitoring, and human 3D motion modeling [78][79][80]. These data can be used for real-time detection of human health or human–computer interaction [81][82]. Wen et al. [22] manufactured a transparent and stretchable wrinkled (maximum strain

• can monitor the training status of athletes in real time and provide training suggestions [83]. TENGs have high sensitivity, and a slight strain can cause the output signal of TENGs to change. Self-powered sensors based on TENGs are feasible signal monitoring sensors for facial activity, breathing

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• many samples can be performed. In fact, at doses below the threshold for nanobubble formation, the introduction of helium atoms into interstitial sites can be used to delicately induce strain into a crystal lattice, which can be leveraged for strain engineering. And at higher doses, localized and

• controlled surface swelling can be used to create 3D structures from an initially flat substrate, that is, ion implantation using the HIM can also be used for nanofabrication. Strain engineering When helium ions are implanted into a crystal lattice they insert as atoms into interstitial sites, and due to

• their chemical inertness, do not react with the material. This interstitial placement induces strain into the lattice and hence offers a method for so-called strain engineering of a range of physical properties. Very recently, ion implantation using the HIM has been investigated for this purpose

Properties of graphene deposited on GaN nanowires: influence of nanowire roughness, self-induced nanogating and defects

• Jakub Kierdaszuk,
• Piotr Kaźmierczak,
• Justyna Grzonka,
• Aleksandra Krajewska,
• Aleksandra Przewłoka,
• Wawrzyniec Kaszub,
• Zbigniew R. Zytkiewicz,
• Marta Sobanska,
• Maria Kamińska,
• Andrzej Wysmołek and
• Aneta Drabińska

Beilstein J. Nanotechnol. 2021, 12, 566–577, doi:10.3762/bjnano.12.47

• nanowires impact graphene properties such as roughness, strain, and carrier concentration as well as density and type of induced defects. Tracing the manifestation of those interactions is important for the application of novel heterostructures. A detailed analysis of Raman spectra of graphene deposited on

• different nanowire substrates shows that bigger differences in nanowires height increase graphene strain, while a higher number of nanowires in contact with graphene locally reduces the strain. Moreover, the value of graphene carrier concentration is found to be correlated with the density of nanowires in

• graphene on rarely distributed nanowires. Our results also show modification of graphene carrier concentration and strain by different types of defects present in graphene. Therefore, the nanowire substrate is promising not only for strain and carrier concentration engineering but also for defect

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• ) [19][20], strain-induced highly corrugated layers for h-BN/Rh(111) [21][22][23], and template layers for molecules with strong local variations of the work function for h-BN/Ir(111) [24] are representative of such morphological diversity. We use low-temperature combined scanning tunnelling (STM) and

• than the one studied in this work, the extremely low stiffness of only approx. 1 N·m−1 at the weakly bound rim areas confirmed the buckling of the monolayer into the third dimension to relieve the strain induced by the significant lattice mismatch of this strongly corrugated van der Waals layer [23

• h-BN/Cu(111) system. We obtain a sheet stiffness of K⟂ = 9.4 ± 0.9 N·m−1, which is one order of magnitude larger than that obtained on h-BN/Rh(111), indicating substantial mechanical stability. The small lattice mismatch between h-BN and Cu(111), compared to h-BN and Rh(111), results in lower strain

A stretchable triboelectric nanogenerator made of silver-coated glass microspheres for human motion energy harvesting and self-powered sensing applications

• Hui Li,
• Yaju Zhang,
• Yonghui Wu,
• Hui Zhao,
• Weichao Wang,
• Xu He and
• Haiwu Zheng

Beilstein J. Nanotechnol. 2021, 12, 402–412, doi:10.3762/bjnano.12.32

• V and ISC = 2.8 μA) with an external load resistance of 2 MΩ. As can be seen from Figure 4e and Figure 4f, the resistance linearly increases from 0.35 to 1.18 Ω/cm2 when the tensile strain reaches 300%. In the process, the thickness of the SCGM layer becomes thinner and the resistance of the S-TENG

• increases linearly. When the S-TENG is further stretched, the slope of the curve falls again because the relative variation of the SCGM layer decreases. After releasing the strain, the resistance is recovered at 0.11 Ω/cm2 resulting from a hysteresis in the rearrangement of the SCGMs. Although the curves

• between sheet resistance and tensile strain have different shapes, the resistance value before and after stretching is of the same order, exhibiting the excellent flexibility and mechanical robustness of the S-TENG. Applications of S-TENG Charging performance and monitoring human motion The electrical

Spontaneous shape transition of Mn_xGe_1−x islands to long nanowires

• S. Javad Rezvani,
• Luc Favre,
• Gabriele Giuli,
• Yiming Wubulikasimu,
• Isabelle Berbezier,
• Augusto Marcelli,
• Luca Boarino and
• Nicola Pinto

Beilstein J. Nanotechnol. 2021, 12, 366–374, doi:10.3762/bjnano.12.30

• tend to ≃80 nm of width. We found that tuning the annealing process allows one to extend the wire length up to ≃1.5 μm with a minor rise of the lateral size to ≃100 nm. The elongation process of the nanostructures is in agreement with a strain-driven shape transition mechanism proposed in the

• properties of the Mn–Ge alloy to design and fabricate novel nanodevices. Keywords: nanowires; semi-metallic Ge–Mn alloy; strain-induced growth; Introduction Metallic and semimetallic nanowires (NWs) have attracted vast interest in nanoscale electronic and spintronic systems due to their thermal [1

• the wires. For instance, Au, generally used as catalyst for the growth of various semiconductor NWs, acts as a deep-level trap in germanium bulk and NWs, modifying the electronic transport properties [5]. Strain-induced elongation is a mechanism [34] that can lead to either epitaxial or endotaxial

Determination of elastic moduli of elastic–plastic microspherical materials using nanoindentation simulation without mechanical polishing

• Hongzhou Li and
• Jialian Chen

Beilstein J. Nanotechnol. 2021, 12, 213–221, doi:10.3762/bjnano.12.17

• case of pileup and too low in the case of sink-in [10]. Nix and Gao deduced the theory of strain gradient plasticity to interpret the “size effect” of indentation as an increase in physical quantity with the decreasing depth of penetration [11]. Experimental results show that the size effect of

• here. Yan established a set of non-dimensional relations for conical indentation on a homogeneous, isotropic semi-infinite flat substrate, including the quantity E/σy [15]. σy is the initial yield stress of a linear elastic, perfectly plastic material. σy/E is the initial yield strain. Phadikar showed

• loads. The loading curves for different indentation depths superpose and follow exactly the same loading curve. The residual depth after complete unloading is larger for deeper indentations. The area under the unloading curve is the reversible elastic strain energy. The area enclosed by the loading and

A review on the biological effects of nanomaterials on silkworm (Bombyx mori)

• Sandra Senyo Fometu,
• Guohua Wu,
• Lin Ma and
• Joan Shine Davids

Beilstein J. Nanotechnol. 2021, 12, 190–202, doi:10.3762/bjnano.12.15

• the silk fibers, enhancing their mechanical properties and promoting silk protein crystallization. This is in line with the research report by Wu et al. [168], who stated that silkworm silk containing Cu exhibited a good tensile strength of 360 MPa and a strain of 38%, which is 89% and 36% higher than

• the values of tensile strength and strain obtained for natural silk fiber (control), respectively. Ma et al. [169] evaluated the effect of vascular injection of graphene quantum dots (GQDs) in silkworm on the mechanical properties of the silk. GQDs are known for their outstanding mechanical properties

• the resulting silk fiber with a mechanical strength of 1.07 GPa and a strain of 16.8% [170]. The effects of bovine serum albumin (BSA)-stabilized gold nanoclusters (BSA-Au NCs) at different concentrations (9.38, 1.88, 0.938, and 0.188 µg) inserted via intravascular injection in the silkworm was

Imaging of SARS-CoV-2 infected Vero E6 cells by helium ion microscopy

• Natalie Frese,
• Patrick Schmerer,
• Martin Wortmann,
• Matthias Schürmann,
• Matthias König,
• Michael Westphal,
• Friedemann Weber,
• Holger Sudhoff and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 172–179, doi:10.3762/bjnano.12.13

• modified Eagle's medium (Thermo Fisher Scientific) supplemented with 10% fetal bovine serum (Capricorn Scientific) in a 5% CO2 atmosphere at 37 °C. SARS-CoV-2 (strain SARS-CoV-2 /München-1.2/2020/984, p.2) [26] was grown on Vero E6 cells and titrated as described [27]. Infection experiments were done under

Paper-based triboelectric nanogenerators and their applications: a review

• Jing Han,
• Nuo Xu,
• Yuchen Liang,
• Mei Ding,
• Junyi Zhai,
• Qijun Sun and
• Zhong Lin Wang

Beilstein J. Nanotechnol. 2021, 12, 151–171, doi:10.3762/bjnano.12.12

• . designed a soft deployable reflector for optical beam steering using kirigami [133]. As shown in Figure 7a, the planar soft deployable structure is made of uniform hollow pockets in which the kirigami reflective films are inlaid. As the axial strain is increased during stretching, the surfaces of the

• ) that can effectively operate under tensile strain conditions and with an applied contact force [135]. The Wang group developed a highly stretchable interlocking kirigami TENG (K-TENG) based on inelastic paper materials [136]. K-TENGS are capable of harvesting mechanical energy from various types of

• strain of up to 200% without breaking. The typical electrical output of a K-TENG under cyclic stretching of up to specific tensile strain values of 16%, 28%, and 40% were tested. When the tensile strain of a given K-TENG was at 16% or 28%, the Voc and the transfered charge (Qtr) increased monotonically

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

• enough to allow for a stable small-amplitude operation [1]. The equivalent stiffness keq of the qPlus sensor is shown in Figure 8, which is calculated from the strain energy and the tip amplitude with an equivalent point-mass model [28]. We see in Figure 8c that for a 0.075 mm tip, there is an optimal

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

• abstract of LeTourneau et al. on rhizobacterial biofilms in the proceedings of Microscopy and Microanalytics 2015 [89]. On wheat roots, they grew a phenazine-1-carboxylic acid (PCA)-producing fluorescent pseudomonad strain and an isogenic mutant impaired in the synthesis of PCA. The formation of the

Free and partially encapsulated manganese ferrite nanoparticles in multiwall carbon nanotubes

• Saja Al-Khabouri,
• Salim Al-Harthi,
• Toru Maekawa,
• Mohamed E. Elzain,
• Ashraf Al-Hinai,
• Ahmed D. Al-Rawas,
• Abbsher M. Gismelseed,
• Ali A. Yousif and
• Myo Tay Zar Myint

Beilstein J. Nanotechnol. 2020, 11, 1891–1904, doi:10.3762/bjnano.11.170

• . However, MWCNTs straining the partially encapsulated MnFe2O4 nanoparticles play an important role here. The effect of the strain in MWCNTs reflects in a 1% reduction in the lattice parameter of partially encapsulated MnFe2O4 as compared to that of free MnFe2O4. Hence, the interplanar distance values

• nanoparticles compared to free MnFe2O4 nanoparticles. Upon attachment, evidence of electron transfer from MWCNTs to MnFe2O4 was observed. An increase in the hyperfine field of MnFe2O4/MWCNTs compared to free manganese ferrite nanoparticles was also detected. This can be assigned to two factors: strain from the

Kondo effects in small-bandgap carbon nanotube quantum dots

• Patryk Florków,
• Damian Krychowski and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2020, 11, 1873–1890, doi:10.3762/bjnano.11.169

• ][46][47], other perturbations such as axial strain or twists can shift the dispersion cones in CNTs and open the bandgap [44][48][49][50]. Unlike the quantization bandgaps, which depend on the inverse of the diameter, these narrow perturbation gaps are inversely proportional to the square of the

• changes of the bandgap. In the following we show how, for a given nearly metallic nanotube, one can change the position of high-symmetry points by strain and a magnetic field. Our calculations also show that in a quantum dot formed in a small-bandgap nanotube electron and hole states can degenerate in

• occupation areas by changing the magnetic field and the value of the bandgap; the latter change can be induced by strain. The examples of SU(3) lines drawn for CNTQD(15,12) for several assumed SO parameters are presented in Figure 4. The required magnetic field for the occurrence of threefold degeneracy for

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

• synthesize AlGaN/AlN/GaN heterojunction NWs with controllable size. A single NW is transferred to a flexible poly(ethylene terephthalate) substrate and fixed by indium tin oxide electrodes to form an ohmic contact for the strain sensor. An external mechanical stress is introduced to study the performance of

• the fabricated piezotronic strain sensor. The gauge factor is as high as 30 under compressive or tensile stress, which indicates a high sensitivity of the strain sensor. Periodic strain tests show the high stability and repeatability of the sensor. The working mechanism of the strain sensor is

• investigated and systematically analyzed under compressive and tensile strain. Here, we describe a strain sensor that shows a great application potential in wearable integrated circuits, in health-monitoring devices, and in artificial intelligence. Keywords: AlGaN/AlN/GaN nanowires; flexible; piezotronic

Nanocasting synthesis of BiFeO₃ nanoparticles with enhanced visible-light photocatalytic activity

• Thomas Cadenbach,
• Maria J. Benitez,
• A. Lucia Morales,
• Cesar Costa Vera,
• Luis Lascano,
• Francisco Quiroz,
• Alexis Debut and
• Karla Vizuete

Beilstein J. Nanotechnol. 2020, 11, 1822–1833, doi:10.3762/bjnano.11.164

• very narrow particle size distribution. The results also suggest that the nanoparticles are characterized by a low concentration of surface defects and a low level of local strain, which is ideal for surface-based applications such as photocatalysis. This is confirmed by the reaction kinetics of the

• sized particles. This behavior can be attributed to a low concentration of surface defects and low local strain. The photocatalyst proved to be stable under visible-light irradiation as it could be reapplied successfully in five successive photocatalytic degradation experiments without loss of

Nanomechanics of few-layer materials: do individual layers slide upon folding?

• Ronaldo J. C. Batista,
• Rafael F. Dias,
• Ana P. M. Barboza,
• Alan B. de Oliveira,
• Taise M. Manhabosco,
• Thiago R. Gomes-Silva,
• Matheus J. S. Matos,
• Andreij C. Gadelha,
• Cassiano Rabelo,
• Luiz G. L. Cançado,
• Ado Jorio,
• Hélio Chacham and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2020, 11, 1801–1808, doi:10.3762/bjnano.11.162

• thickness range. In contrast, tip-enhanced Raman spectroscopy measurements on edges in folded graphene flakes, 14 layers thick, show no significant strain. This indicates that layers in graphene flakes, up to 5 nm thick, can still slip to relieve stress, showing the richness of the effect in 2D systems. The

• at the inner part of the fold will have a compressive in-plane strain, and those at the outer part will have a tensile in-plane strain. The compressive and tensile strains could modify the vibrational properties of a fold compared to those of the (flat) bulk of the flake. This should be applicable to

• any 2D material and not restricted to talc. This hypothesis was investigated employing a near-field tip-enhanced Raman spectroscopy (TERS) setup [36][37] that can probe strain variations across the edge of a folded graphene flake of 5 nm thickness (see Supporting Information File 1, section “Near

Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

• Serguei Chiriaev,
• Luciana Tavares,
• Vadzim Adashkevich,
• Arkadiusz J. Goszczak and
• Horst-Günter Rubahn

Beilstein J. Nanotechnol. 2020, 11, 1693–1703, doi:10.3762/bjnano.11.151

• irradiation-induced mechanical strain in the patterning process are elaborated and discussed. Keywords: direct patterning; focused helium ion beam; out-of-plane nanopatterning; polymers; thin films; Introduction Micro- and nanofabrication with focused ion beams (FIBs) is currently a subject of strong

• 1.32 to 2.97 MPa [28], provides a long-range strain relaxation when compared to a short-range strain relaxation in non-elastic polymers, such as PMMA and PC. Therefore, instead of directly projecting the initially flat surface to another depth position, the irradiation-induced strain warps the pristine

• surface. The existence of long-range strain fields, sufficient for a significant deformation in the surface of our PDMS samples, is identified by the observation of ripple patterns around the irradiated areas. Other features associated with the strain fields in highly elastic materials are the sharp

Piezoelectric sensor based on graphene-doped PVDF nanofibers for sign language translation

• Shuai Yang,
• Xiaojing Cui,
• Rui Guo,
• Zhiyi Zhang,
• Shengbo Sang and
• Hulin Zhang

Beilstein J. Nanotechnol. 2020, 11, 1655–1662, doi:10.3762/bjnano.11.148

• concentrations. (c) FTIR spectra of the PVDF fibers. (d) XRD patterns of the PVDF fibers. (e) Stress–strain curves of the PVDF fibers. (a) Schematic diagram of the PES under external pressure. (b) Output voltage as a function of the applied pressure for different doping concentrations. (c) Waveforms

Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

• Matías Guerrero Correa,
• Fernanda B. Martínez,
• Cristian Patiño Vidal,
• Camilo Streitt,
• Juan Escrig and
• Carol Lopez de Dicastillo

Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129

• antibacterial activities against E. coli, P. aeruginosa, methicillin-sensitive and resistant S. aureus [117]. Suganya et al. (2018) developed a potent antifungal nanocomposite with NiO NPs against the Aspergillus niger strain. The authors attributed the excellent antifungal properties to the physical process

On the frequency dependence of viscoelastic material characterization with intermittent-contact dynamic atomic force microscopy: avoiding mischaracterization across large frequency ranges

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 1409–1418, doi:10.3762/bjnano.11.125

• ), is the retardance of the material, relating stress and strain, and R is the indenter radius. The indentation and load are available from the force–distance curve, and an expression for can be easily derived for the Generalized Voigt or Maxwell models (Figure 1), whereby the constants of springs and

• ][35]. Mechanical model diagrams representing the relationship between stress and strain in the complex plane for a linear viscoelastic material with multiple characteristic times [33]. (a) Generalized Voigt or Kelvin model, (b) Generalized Maxwell or Wiechert model, both describing arrheodictic

• transformed strain is generally regarded as the excitation and the transformed stress as the response; in (b) the opposite generally occurs. (a) Storage moduli and (b) and loss moduli as function of frequency for two hypothetical materials, the Generalized Maxwell model parameters of which are provided in

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• the second layer (model in Figure 2f-7,8) leads to the dark variation (Figure 2f). The latter has been reported to cause less lattice strain [74], matching our observation of less distortions in the STHM and nc-AFM images near the missing dimer (Figure 2f-4,5,6 compared to Figure 2g-4,5,6 and shown in

• in which the unsatisfied bonds of the back bonded Si atoms are terminated with hydrogen. As such, any lattice strain is reduced and the neighbouring dimers show minimal variation compared to the defect free profile. Conversely, the maxima of the bright missing dimer in Figure 3k,l is accompanied by

• two local minima “shoulders”. These have a less negative frequency shift, with the minima pulled spatially towards the centre of the defect. We propose that this observation is a result of the second layer Si atoms forming dimer bonds at the defect location, introducing horizontal lattice strain. This

Gram-scale synthesis of splat-shaped Ag–TiO₂ nanocomposites for enhanced antimicrobial properties

• Mohammad Jaber,
• Asim Mushtaq,
• Kebiao Zhang,
• Jindan Wu,
• Dandan Luo,
• Zihan Yi,
• M. Zubair Iqbal and
• Xiangdong Kong

Beilstein J. Nanotechnol. 2020, 11, 1119–1125, doi:10.3762/bjnano.11.96

• Gram-positive Staphylococcus aureus (S. aureus) (ATCC 6538) and Gram-negative Escherichia coli (E. coli) (ATCC 8099) were obtained from the Shanghai Amoy Strain Biotechnology Co. (Shanghai, China). The disc diffusion method was applied to check the antibacterial activity of the prepared pure TiO2 NPs

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

• piezoelectric doubly curved nanoshells and orthotropic piezoelectric cylindrical nanoshells [23][24]. Wang utilized surface strain gradient elasticity to study a meticulous solution to the anti-plane shear problem of a circular elastic inhomogeneity [25]. Nami et al. utilized nonlocal elasticity theory and

• trigonometric shear deformation theory to investigate the static analysis of rectangular nanoplates [26]. The Gurtin–Murdoch surface theory is presented by Sigaeva et al. to study the universal model describing plane strain bending of a multilayered sector of a cylindrical tube [27]. Karimipour et al. presented

• a modified strain gradient theory (MSGT) and Gurtin–Murdoch surface elasticity to investigate the size-dependent nonlinear pull-in instability [28]. A new size-dependent nonlinear model for the analysis of the behavior of carbon nanotube resonators was introduced by Farokhi et al. based on modified