Theoretical investigations of oxygen vacancy effects in nickel-doped zirconia from ab initio XANES spectroscopy at the oxygen K-edge

• Dick Hartmann Douma,
• Lodvert Tchibota Poaty,
• Alessio Lamperti,
• Stéphane Kenmoe,
• Abdulrafiu Tunde Raji,
• Alberto Debernardi and
• Bernard M’Passi-Mabiala

Beilstein J. Nanotechnol. 2022, 13, 975–985, doi:10.3762/bjnano.13.85

• ; Introduction The search for room-temperature magnetic semiconductors has been the driving force behind the increasing interest of material scientists and solid-state physicists in magnetic oxides [1]. This is due to their potential applications as building block of spintronic devices. Magnetic oxides are

Interaction between honeybee mandibles and propolis

• Leonie Saccardi,
• Franz Brümmer,
• Jonas Schiebl,
• Oliver Schwarz,
• Alexander Kovalev and
• Stanislav Gorb

Beilstein J. Nanotechnol. 2022, 13, 958–974, doi:10.3762/bjnano.13.84

• radii of the circles were measured and then averaged. The effective elastic modulus and pull-off force of propolis were measured with a microforce measurement device (Basalt-01; Tetra GmbH, Ilmenau, Germany) [22][23][24]. The device mainly consists of micromanipulators as a platform holding the

• the substrate and retracted from the surface as soon as the load force reached 5 mN. The load was chosen to resemble the force applied by bees when handling propolis. As no studies exist on mandibular forces and pressures of honeybees, pressures measured at the tip of mandibles of predacious

• coleoptera [25] where used as a reference point. Tip pressures were calculated as suggested by [25]: where Fa is the applied force and A is the contact area obtained from the contact radius. With each propolis sample, a set of ten single measurements was performed, each on a different spot on the spoon

Design of a biomimetic, small-scale artificial leaf surface for the study of environmental interactions

• Miriam Anna Huth,
• Axel Huth,
• Lukas Schreiber and
• Kerstin Koch

Beilstein J. Nanotechnol. 2022, 13, 944–957, doi:10.3762/bjnano.13.83

• secondary electron detector. The working distance was 4–7 mm. Atomic force microscopy analysis of recrystallized structures The thickness of the wax coating on glass (1400 µg) was examined with an atomic force microscope (AFM, NanoWizard II, JPK instruments, Berlin, Germany). For this purpose, the

Comparing the performance of single and multifrequency Kelvin probe force microscopy techniques in air and water

• Jason I. Kilpatrick,
• Emrullah Kargin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2022, 13, 922–943, doi:10.3762/bjnano.13.82

• governing the performance of single and multifrequency Kelvin probe force microscopy (KPFM) techniques in both air and water. Metrics such as minimum detectable contact potential difference, minimum required AC bias, and signal-to-noise ratio are compared and contrasted both off resonance and utilizing the

• liquid environments whilst needing the smallest AC bias for operation. Keywords: AFM; atomic force microscopy; closed loop; Kelvin probe force microscope; KPFM; open loop; performance; signal-to-noise ratio; Introduction Atomic force microscopy (AFM) is an enabling technique for the nanoscale mapping

• of topography and surface properties of interfaces in a wide range of environments [1]. Kelvin probe force microscopy (KPFM) utilizes the application of a bias and a conductive probe to map the local electrical properties of an interface at the nanoscale [2], allowing for the determination of the

Micro-structures, nanomechanical properties and flight performance of three beetles with different folding ratios

• Jiyu Sun,
• Pengpeng Li,
• Yongwei Yan,
• Fa Song,
• Nuo Xu and
• Zhijun Zhang

Beilstein J. Nanotechnol. 2022, 13, 845–856, doi:10.3762/bjnano.13.75

• was found that the wing folding ratio correlated with the lift force of the beetles. Wind speed, folding ratio, aspect ratio, and flapping frequency had a combined effect on the flight performance of the beetles. The results will be helpful to design new deployable FWMAVs. Keywords: beetle hind wings

• insects in flight and to imitate the flight of insects [14][15]. Insect wings play a major role here. Hence, examining their flight parameters is crucially important to design biomimetic FMAVs [16][17]. It is increasingly clear that most insects obtain useful force with the help of aerodynamic mechanisms

• , it was found that their flexibility can increase their mean lift coefficient [21]. In rhinoceros beetles, the elytra is also involved in aerodynamics during takeoff, producing an interaction force between the elytra and the hind wings [22]. To avoid damage or hinder the movement on the ground, the

Temperature and chemical effects on the interfacial energy between a Ga–In–Sn eutectic liquid alloy and nanoscopic asperities

• Yujin Han,
• Pierre-Marie Thebault,
• Corentin Audes,
• Xuelin Wang,
• Haiwoong Park,
• Jian-Zhong Jiang and
• Arnaud Caron

Beilstein J. Nanotechnol. 2022, 13, 817–827, doi:10.3762/bjnano.13.72

• interfacial energies between a eutectic Ga–In–Sn liquid alloy and single nanoscopic asperities of SiOx, Au, and PtSi have been determined in the temperature range between room temperature and 90 °C by atomic force spectroscopy. For all asperities used here, we find that the interfacial tension of the eutectic

• increase of the interfacial energy as a function of the temperature, which can be explained by the reactivity between SiOx and Ga and the occurrence of chemical segregation at the liquid alloy surface. Keywords: atomic force microscopy (AFM); interfacial energy; liquid alloy; Introduction Recently, room

• could be tuned by texturing the substrate surface. The wetting of gallium-based liquid alloys is thus complex and depends on the stability of the oxide at the liquid–substrate interface, the reactivity with the substrate material, and the substrate topography. In this work, we applied atomic force

Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production

• Chun-Da Liao,
• Andrea Capasso,
• Tiago Queirós,
• Telma Domingues,
• Fatima Cerqueira,
• Nicoleta Nicoara,
• Jérôme Borme,
• Paulo Freitas and
• Pedro Alpuim

Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70

• , whereas C1 provided proper support while maintaining a low residue level. The length of the PMMA molecular chains (proportional to molecular weight and the attractive intermolecular force) appeared to be the determining factor in the mechanical strength (as demonstrated by C3 PMMA, enabling eight complete

• analyzer had a pass energy of 20 eV. Atomic force microscopy The surface topographies of graphene were investigated by a Bruker Dimension Icon atomic force microscope (AFM), using PPP-NCH (NanosensorsTM) cantilevers with a tip radius smaller than 20 nm, a force constant of 42 N/m, and 250 kHz resonance

• frequency. The AFM measurement was carried out in tapping mode. A 633 nm laser light aimed at the back side of the cantilever tip was reflected toward a position-sensitive photodetector, which provides feedback signals to piezoelectric scanners that maintain the cantilever tip at constant height (force

Efficient liquid exfoliation of KP₁₅ nanowires aided by Hansen's empirical theory

• Zhaoxuan Huang,
• Zhikang Jiang,
• Nan Tian,
• Disheng Yao,
• Fei Long,
• Yanhan Yang and
• Danmin Liu

Beilstein J. Nanotechnol. 2022, 13, 788–795, doi:10.3762/bjnano.13.69

• concentration, centrifugation was not used. Measurement equipment UV−visible spectrophotometry was performed by using a Shimadzu UV-3101PC system. Atomic force microscopy (AFM) tests were performed in a Multimode 8 system. The Raman tests were performed on a WITec alpha300 RA confocal Raman microscopy system

• coefficient and the Hansen solubility parameters for KP15 According to the Hansen’s theory [19], the dispersed concentration C of a KP15 dispersion prepared by liquid exfoliation can be expressed by Equation 1 as follows. where δD is the intermolecular dispersion force, δH is the intermolecular hydrogen bond

• ; δP is the intermolecular polar force; δA,D, δA,P, δA,H are the Hansen solubility parameters (HSPs) of the solute; and δB,D, δB,P, δB,H are the HSPs of the solvent. Therefore, to get a high concentration of KP15 in dispersion, the HSPs of the solvent for the exfoliation of KP15 should be close to

Gelatin nanoparticles with tunable mechanical properties: effect of crosslinking time and loading

• Agnes-Valencia Weiss,
• Daniel Schorr,
• Julia K. Metz,
• Metin Yildirim,
• Saeed Ahmad Khan and
• Marc Schneider

Beilstein J. Nanotechnol. 2022, 13, 778–787, doi:10.3762/bjnano.13.68

• . Keywords: atomic force microscopy; drug delivery; elasticity; gelatin nanoparticles; Young’s modulus; Introduction Developing nanoparticulate drug carriers for various diseases and application routes requires establishing controllable systems, matching the needs of the respective application to achieve

• extract the height image from the force–distance curves acquired at each pixel. Particles were well distributed on substrates showing no agglomeration and a narrow size distribution. GNPs occur with a smooth surface and are spherically shaped when measured under liquid conditions. Particles crosslinked

• experimental triplicate. Atomic force microscopy For AFM measurements, GNPs were electrostatically fixed on positively coated silica specimens. Samples for AFM measurements were prepared according to the following protocol: Silica wafers were cleaned in an ultrasonic bath (Elmasonic B, Elma Schmidbauer GmbH

Recent advances in nanoarchitectures of monocrystalline coordination polymers through confined assembly

• Lingling Xia,
• Qinyue Wang and
• Ming Hu

Beilstein J. Nanotechnol. 2022, 13, 763–777, doi:10.3762/bjnano.13.67

• alignments. For instance, monodispersed colloidal particles can assemble through the evaporation of droplets [56][57]. The local flow and equilibrium interactions among the particles force the obtained assemblies to have periodic structures. The ordered colloidal crystals can regulate the transmission

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• photocatalytic semiconductors. The local SPV is generally measured consecutively by Kelvin probe force microscopy (KPFM) in darkness and under illumination, in which thermal drift degrades spatial and energy resolutions. In this study, we propose the method of AC bias Kelvin probe force microscopy (AC-KPFM

• modulated external disturbances. Keywords: atomic force microscopy; Kelvin probe force microscopy; photocatalyst; surface photovoltage; titanium dioxide; Introduction Surface photovoltage (SPV) is the change in surface potential caused by light illumination [1][2] and is measured to determine such

• features as band bending [3][4], the lifetimes of excited carriers [5][6][7], the minority carrier diffusion length [8][9], and the plasmonic effect [10][11][12]. The local SPV is usually measured by Kelvin probe force microscopy (KPFM) [13][14][15][16][17][18][19][20][21], which is based on atomic force

Reliable fabrication of transparent conducting films by cascade centrifugation and Langmuir–Blodgett deposition of electrochemically exfoliated graphene

• Teodora Vićentić,
• Stevan Andrić,
• Vladimir Rajić and
• Marko Spasenović

Beilstein J. Nanotechnol. 2022, 13, 666–674, doi:10.3762/bjnano.13.58

• electrochemical exfoliation, whereby graphene is exfoliated in an electrolyte from an electrode made of graphite [19]. In electrochemical exfoliation, ions from the electrolyte flow towards the graphite electrode and intercalate between the graphene layers. The electrochemical reaction provides a driving force to

• the solvent of choice because of its favorable properties regarding LB deposition [14]. 1 mL of dispersion was initially centrifuged at a rate of 1500 rpm (relative centrifugal force, RCF, equal to 206g). The obtained centrifugation sediment contained the largest nanosheets of the initial dispersion

• wavelength of 660 nm and the number of graphene layers was calculated for each sample, taking into account an absorption of 2.3% for each layer of graphene, as in the work by Bonaccorso and co-workers [43]. Although atomic force microscopy (AFM) is often employed to characterize graphene films [2][12][14][44

Fabrication and testing of polymer microneedles for transdermal drug delivery

• Vahid Ebrahiminejad,
• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2022, 13, 629–640, doi:10.3762/bjnano.13.55

• characteristics such as operating temperature, axial force range, and embossing time depend on material properties, geometrical size, and complexity, requiring multiple optimization studies. MN arrays must be capable of being handled without risk of damage and must penetrate the skin with low force to the

• normal insertion of MNs, the applied force is linearly increased to the moment of rupture, which breaks the skin’s SC layer, followed by a sudden drop in the force-displacement graph [19][20]. However, the MN can be subjected to sudden excessive axial or lateral loads, which may induce early failure of

• , hence improving overall insertion safety. For the MN insertion to be mechanically safe, the safety margin (SM), which is the ratio of failure force to insertion force, should be maximized and greater than unity (SM > 1) [22]. MNs must penetrate deep enough into the skin layers to enable an effective

Comparative molecular dynamics simulations of thermal conductivities of aqueous and hydrocarbon nanofluids

• Adil Loya,
• Antash Najib,
• Fahad Aziz,
• Asif Khan,
• Guogang Ren and
• Kun Luo

Beilstein J. Nanotechnol. 2022, 13, 620–628, doi:10.3762/bjnano.13.54

• constructed with 36 CuO molecules bonded by the COMPASS force field. This constructed nanoparticle size was 0.4 nm, as shown in Figure 1b. A molecular dynamics simulation of paraffin (i.e., eicosane C20H42) was also conducted for comparison with the aqueous solution. In the alkane/CuO nanofluid simulation

• incorporated using the COMPASS force field [50]. Moreover, it is known from the literature that the COMPASS force field has already been used for alkanes and benzene-based systems. Therefore, this force field proved to be an accurate approach for the alkane-based fluidic system in this work [50]. The paraffin

• constructed for molecular dynamics was a straight-chain alkane molecule. The COMPASS force field was applied using the Material Studio. The alkane radius is decreased in the figure for a clearer visualization so that the nanoparticles can be clearly illustrated and identified. Both systems (i.e., nonaqueous

Quantitative dynamic force microscopy with inclined tip oscillation

• Philipp Rahe,
• Daniel Heile,
• Reinhard Olbrich and
• Michael Reichling

Beilstein J. Nanotechnol. 2022, 13, 610–619, doi:10.3762/bjnano.13.53

• Philipp Rahe Daniel Heile Reinhard Olbrich Michael Reichling Fachbereich Physik, Universität Osnabrück, Barbarastrasse 7, 49076 Osnabrück, Germany 10.3762/bjnano.13.53 Abstract In the mathematical description of dynamic atomic force microscopy (AFM), the relation between the tip–surface normal

• interaction force, the measurement observables, and the probe excitation parameters is defined by an average of the normal force along the sampling path over the oscillation cycle. Usually, it is tacitly assumed that tip oscillation and force data recording follows the same path perpendicular to the surface

• the tip movement can have critical consequences for data interpretation, especially for measurements on nanostructured surfaces exhibiting significant lateral force components. Inclination effects are illustrated by simulation results that resemble the representative experimental conditions of

Sodium doping in brookite TiO₂ enhances its photocatalytic activity

• Boxiang Zhuang,
• Honglong Shi,
• Honglei Zhang and
• Zeqian Zhang

Beilstein J. Nanotechnol. 2022, 13, 599–609, doi:10.3762/bjnano.13.52

• interplanar spacing values are 3.5092 and 3.4619 Å, respectively. Thus, the orientation relationship between the matrix and twins is // and // The twinning effect in the brookite structure may be the major driven force of the phase transformation from the brookite NaxTi1−xO2 to Na2Ti6O13. Such transformation

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• the optical contrast, one can estimate that the thickness of the more transparent areas of the MoSe2 flake is smaller than that of other regions. To visualize the CuPc molecule distribution on the MoSe2 flake, atomic force microscopy (AFM) was used, and the results are shown in Figure 1b. The insets

• images of CuPc/MoSe2. The topographic images of CuPc/MoSe2 are obtained with an atomic force microscope (Multimode 8-HR, Bruker) operated in peak force tapping mode using a SCANASYST-AIR probe (silicon tip on nitride lever, Bruker). Optical properties of a triangular MoSe2 flake covered with a thin film

Effects of substrate stiffness on the viscoelasticity and migration of prostate cancer cells examined by atomic force microscopy

• Xiaoqiong Tang,
• Yan Zhang,
• Jiangbing Mao,
• Yuhua Wang,
• Zhenghong Zhang,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2022, 13, 560–569, doi:10.3762/bjnano.13.47

• unclear how mechanical properties regulate the cellular response to the environmental matrix. In this study, atomic force microscopy (AFM) and laser confocal imaging were used to qualitatively evaluate the relationship between substrate stiffness and migration of prostate cancer (PCa) cells. Cells

• . Analysis of AFM force–distance curves indicated that the elasticity of the cells cultured on 35 kPa substrates increased while the viscosity decreased. Wound-healing experiments showed that PCa cells cultured on 35 kPa substrates have higher migration potential. These phenomena suggested that the

• substrate stiffness and the mechanical properties of cells in prostate tumour metastasis, providing a basis for understanding the changes in the biomechanical properties at a single-cell level. Keywords: actin cytoskeleton; atomic force microscopy; migration; prostate cancer cells; substrate stiffness

Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections

• Sharif Abdelghany,
• Walhan Alshaer,
• Yazan Al Thaher,
• Maram Al Fawares,
• Amal G. Al-Bakri,
• Saja Zuriekat and
• Randa SH. Mansour

Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43

• array, as shown in Figure 5. The ability of microneedles to withstand the insertion force is crucial in topical and transdermal delivery systems [47]. Compressing the microneedles with a thumb press revealed no significant difference in the height of CIP_MN1 or CIP_MN2 before and after thumb press for

• 30 s on excised human skin. This indicates that both microneedle formulations withstand the insertion force required for microneedle application on skin. We used thumb press to study the tensile strength of the microneedles since, previously, dissolving polymeric microneedles composed of PVA have

• required insertion force in skin [51][52]. Microneedle dissolution in human skin The dissolution of CIP_MN1 in human skin showed a gradual decrease in the microneedle length with time. The microneedles required one hour for complete dissolution in the skin as shown in Figure 6. The dissolution of CIP_MN1

Design and characterization of polymeric microneedles containing extracts of Brazilian green propolis

• Camila Felix Vecchi,
• Rafaela Said dos Santos,
• Jéssica Bassi da Silva and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2022, 13, 503–516, doi:10.3762/bjnano.13.42

• analysis of the results obtained for the measurements of microneedles are given in Table 2. As the base width/height ratio decreased, the failure force decreased as well. This can be observed by the MNs E5, which have the lowest compression force of the MNs containing EE and an aspect ratio of 1:7 (base

• width/height) while the MNs E9 have the highest compression value and an aspect ratio of 1:6 (base width/height). Römgens and colleagues also observed that with an increase in the diameter of the MN tips, the force for insertion increases [42]. When different MN tip diameters were studied for insertion

• The 18 formulations were analyzed for compression force and compression area on a hard glass surface (Petri dish). The results are displayed in Table 3. Regarding the compression force, for MNs containing EE, only the extract showed positive significant interference, where higher values of compression

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• tilting or randomly moving some or all molecules and by either removing some of the atoms or whole molecules to, for example, mimic defects in the experimental process (randomization). (3) The electron irradiation was modeled by a vertical force gradient being applied to the atoms; it is linear and

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• . The voltage between the plates creates an electrostatic force that causes the upper plate to move down, and the spring provides a restoring force that prevents it from moving. When the applied voltage is lower than the pull-in voltage, the electrostatic force and mechanical recovery force on the upper

• or bottom-up processes and, subsequently, their parameters are tested. In the latter, the pull-in effect of NWs is directly studied through atomic force microscopy or transmission electron microscopy using nanomanipulators. This allows one to explore different working states without having to

• . Based on the coupling of triboelectrification and electrostatic induction, the switch can be used as a triboelectric generator (TEG) [90]. The TEG usually contains an insulated diaphragm and the switch is normally closed. The combination of triboelectrification and the elastic restoring force causes the

Micro- and nanotechnology in biomedical engineering for cartilage tissue regeneration in osteoarthritis

• Zahra Nabizadeh,
• Mahmoud Nasrollahzadeh,
• Hamed Daemi,
• Mohamadreza Baghaban Eslaminejad,
• Ali Akbar Shabani,
• Mehdi Dadashpour,
• Majid Mirmohammadkhani and
• Davood Nasrabadi

Beilstein J. Nanotechnol. 2022, 13, 363–389, doi:10.3762/bjnano.13.31

Controllable two- and three-state magnetization switching in single-layer epitaxial Pd_1−xFe_x films and an epitaxial Pd_0.92Fe_0.08/Ag/Pd_0.96Fe_0.04 heterostructure

• Igor V. Yanilkin,
• Amir I. Gumarov,
• Gulnaz F. Gizzatullina,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2022, 13, 334–343, doi:10.3762/bjnano.13.28

• of spin waves in high magnetic fields [27]. At low temperatures, this effect is usually small, and a positive magnetoresistance caused by the action of the Lorentz force dominates [27][28]. However, in the Pd0.92Fe0.08 epitaxial film, the electron mean free path is small even at low temperatures and

Interfacial nanoarchitectonics for ZIF-8 membranes with enhanced gas separation

• Season S. Chen,
• Zhen-Jie Yang,
• Chia-Hao Chang,
• Hoong-Uei Koh,
• Sameerah I. Al-Saeedi,
• Kuo-Lun Tung and
• Kevin C.-W. Wu

Beilstein J. Nanotechnol. 2022, 13, 313–324, doi:10.3762/bjnano.13.26

• measurements of N2 and CO2, the membrane was swept by the target gas for at least 10 min to remove other gaseous species from the measurement system. Then, the side of the ZIF-8 selective layer was fed with pressurized target gas to provide a driving force for the gas to permeate through the membrane. The