Mobility of charge carriers in self-assembled monolayers

• Zhihua Fu,
• Tatjana Ladnorg,
• Hartmut Gliemann,
• Alexander Welle,
• Asif Bashir,
• Michael Rohwerder,
• Qiang Zhang,
• Björn Schüpbach,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235

• island with the particle analysis of the SPIP software (version 6.7.8) by setting the threshold current to 1 pA. (ii) Then – assuming a circular island shape – the island diameter d was computed from the area A using d = 2∙(A/π)1/2. (iii) Finally the center current of each island was plotted as a

Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness

• Cynthia Kembuan,
• Maysoon Saleh,
• Bastian Rühle,
• Ute Resch-Genger and
• Christina Graf

Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231

• increases as the amount of TEOS increases, while core-free silica NPs appear when the TEOS content exceeds the threshold of homogeneous nucleation [36][39][47][48][49]. Typically, a maximum diameter <50 nm can be reached with this technique [23]. Microemulsion growth processes are usually slow and laborious

• formation of new micelles [23]. Ding et al. linked these considerations to the theory of LaMer [36]. According to the LaMer theory, heterogeneous nucleation occurs when the supersaturation of the growth species is below the homogeneous nucleation threshold but above the heterogeneous nucleation threshold

• , while a higher supersaturation (above the homogeneous nucleation threshold) leads to simultaneous heterogeneous and homogeneous nucleation. In general, the processes leading to homogeneous and heterogeneous nucleation and growth in such reverse microemulsion systems are complex and depend on numerous

Integration of sharp silicon nitride tips into high-speed SU8 cantilevers in a batch fabrication process

• Nahid Hosseini,
• Matthias Neuenschwander,
• Oliver Peric,
• Santiago H. Andany,
• Jonathan D. Adams and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2019, 10, 2357–2363, doi:10.3762/bjnano.10.226

• results exclusively from the tip geometry, the noise suppression threshold is set at 100 pm which is superior to the measured image noise of 40 pm. Additionally, borders of the image are also excluded from the estimation to prevent edge artefacts. The inset of Figure 2a shows the result of the Gwyddion

Four self-made free surface electrospinning devices for high-throughput preparation of high-quality nanofibers

• Yue Fang and
• Lan Xu

Beilstein J. Nanotechnol. 2019, 10, 2261–2274, doi:10.3762/bjnano.10.218

• maximal. The jet initiation in the OSFSE process viewed from the side by a high-speed camera is shown in Figure 4. Immediately after a voltage of 40 kV (which is above the threshold voltage) is applied to the solution surface, a deformation of the fluid is observed at the top edge of the solution

Use of data processing for rapid detection of the prostate-specific antigen biomarker using immunomagnetic sandwich-type sensors

• Camila A. Proença,
• Tayane A. Freitas,
• Thaísa A. Baldo,
• Elsa M. Materón,
• Flávio M. Shimizu,
• Gabriella R. Ferreira,
• Frederico L. F. Soares,
• Ronaldo C. Faria and
• Osvaldo N. Oliveira Jr.

Beilstein J. Nanotechnol. 2019, 10, 2171–2181, doi:10.3762/bjnano.10.210

• quantification with the immunosensor is lower than the threshold established for the serum level found in patients with prostate cancer (above 3.6 ng·mL−1 stage A1) [56]. The samples were diluted in PBS for reaching the linear range, providing a response within the stipulated standards for the samples. Using the

The importance of design in nanoarchitectonics: multifractality in MACE silicon nanowires

• Stefania Carapezzi and
• Anna Cavallini

Beilstein J. Nanotechnol. 2019, 10, 2094–2102, doi:10.3762/bjnano.10.204

• and a NW length of 5 μm. For the other sample (labelled SiNW2; Figure 2b) the source substrate was As-doped with a doping density of about 1018 cm−3 and a NW length of 1.3 μm. Figure 3a and Figure 3b are the masked images obtained applying a height threshold on the AFM measurements of Figure 2. The

• threshold divides the surface into two regions: the tips of NWs (black colour) and the remainder of the sample (white colour). The NW tips appear clustered in both samples, creating a very complex architecture over the surfaces. It is noteworthy to observe that this clustering has not been purposefully

• have calculated the critical aspect ratio [31] of the NWs of samples SiNW1 and SiNW2. The critical aspect ratio is a threshold value for the stability of the bundles. NWs with aspect ratios larger than the critical one will remain attached after bending towards each other and getting in contact. Given

Review of advanced sensor devices employing nanoarchitectonics concepts

• Katsuhiko Ariga,
• Tatsuyuki Makita,
• Masato Ito,
• Taizo Mori,
• Shun Watanabe and
• Jun Takeya

Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198

• sensors have a super-Nernstian sensitivity and reference-less nature. This organic charge-modulated field-effect transistor mechanism is attributed to the variation of the threshold voltage in the organic field-effect transistor induced by charge variation upon the presence of a charge (protonation, etc

• A induced the removal of the antibody from the sensor surface through competitive binding, resulting in a capacitance increase accompanied with an increase of the drain current. The switching-on signal response of this system is in the nM range of concentration threshold for bisphenol A detection

Gold-coated plant virus as computed tomography imaging contrast agent

• Alaa A. A. Aljabali,
• Mazhar S. Al Zoubi,
• Khalid M. Al-Batanyeh,
• Ali Al-Radaideh,
• Mohammad A. Obeid,
• Abeer Al Sharabi,
• Walhan Alshaer,
• Bayan AbuFares,
• Tasnim Al-Zanati,
• Murtaza M. Tambuwala,
• Naveed Akbar and
• David J. Evans

Beilstein J. Nanotechnol. 2019, 10, 1983–1993, doi:10.3762/bjnano.10.195

• sample chamber with sterile syringes until the solution reached the tip of the nozzle. Ten 30 s videos using a camera level of 7 and a detection threshold of 5, were recorded for each sample and the software was used to estimate concentration and NP size. Measurements were recorded at ambient temperature

Processing nanoporous organic polymers in liquid amines

• Jeehye Byun,
• Damien Thirion and
• Cafer T. Yavuz

Beilstein J. Nanotechnol. 2019, 10, 1844–1850, doi:10.3762/bjnano.10.179

• structural variety of nanoporous polymers and amines. Properties of COP-100-Film Once COP-100-Film formed, it did not dissolve in any common organic solvents as long as the amount of EDA was within the threshold range, from 10 to 50 equiv of COP-100. The amount of nitrogen in COP-100-Film varied as the EDA

Growth dynamics and light scattering of gold nanoparticles in situ synthesized at high concentration in thin polymer films

• Corentin Guyot,
• Philippe Vandestrick,
• Ingrid Marenne,
• Olivier Deparis and
• Michel Voué

Beilstein J. Nanotechnol. 2019, 10, 1768–1777, doi:10.3762/bjnano.10.172

• threshold method, nanoparticles can be isolated from the polymer matrix image and their shape/size characteristics can be determined (Figure 6). Similar morphological characteristics were also usually observed at a larger scale by optical microscopy and SEM [24]. Recently, the shape of the AuNPs was shown

• ). (A) PVA matrix with embedded in situ synthesized AuNPs (image size: 5 μm × 5 μm). (B) Details of the previous image (image size: 1 μm × 1 μm)). (C) Undoped PVA matrix (image size: 5 μm × 5 μm). Perimeter–area relationship of the AuNPs. Symbols: experimental data determined by using a height-threshold

Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• techniques such as patterning with nanogrooves [13][14][15] and nanoslits [16], ion-beam irradiation of specific inorganic [17] and polymer [18] substrates, subjecting of photo-controlled aligning polymers to near-threshold doses of ultraviolet radiation [19], formation of surface microdomains from

Nanoporous smartPearls for dermal application – Identification of optimal silica types and a scalable production process as prerequisites for marketed products

• David Hespeler,
• Sanaa El Nomeiri,
• Jonas Kaltenbach and
• Rainer H. Müller

Beilstein J. Nanotechnol. 2019, 10, 1666–1678, doi:10.3762/bjnano.10.162

• rutin solution is used and evaporation continues, rutin continues to precipitate on the surface of completely loaded particles. When rutin deposits as a thin layer on the surface, the rutin stays amorphous; when the layer thickness increases above a critical threshold, crystallization occurs which can

Graphynes: an alternative lightweight solution for shock protection

• Kang Xia,
• Haifei Zhan,
• Aimin Ji,
• Jianli Shao,
• Yuantong Gu and
• Zhiyong Li

Beilstein J. Nanotechnol. 2019, 10, 1588–1595, doi:10.3762/bjnano.10.154

• impact velocity values ranging from 1 to 6 km/s. It is found that to perforate the examined α-GY nanosheet, the velocity of the projectile should be larger than a threshold value of ca. 1.6 km/s. For impact velocity values lower than this threshold value, the projectile will be bounced back by the

• nanosheet. Similarly, the threshold velocity for β-GY, γ-GY and 6612-GY are 1.8 km/s, 1.8 km/s, and 1.6 km/s, respectively. Higher impact velocities will induce more severe local deformation, and there will be no time for the stress to develop a well distributed pattern as observed scenarios with in lower

Rapid thermal annealing for high-quality ITO thin films deposited by radio-frequency magnetron sputtering

• Petronela Prepelita,
• Ionel Stavarache,
• Doina Craciun,
• Florin Garoi,
• Catalin Negrila,
• Beatrice Gabriela Sbarcea and
• Valentin Craciun

Beilstein J. Nanotechnol. 2019, 10, 1511–1522, doi:10.3762/bjnano.10.149

• , the ITO films were subjected to RTA in air. This process was performed in an open resistive furnace (MILA 5000) in order to improve the structural and optical properties of the films. Thus, the samples were subjected to 575 °C at a heating rate of 20 °C/s and maintained at the thermal threshold for 10

Magnetic segregation effect in liquid crystals doped with carbon nanotubes

• Danil A. Petrov,
• Pavel K. Skokov,
• Alexander N. Zakhlevnykh and
• Dmitriy V. Makarov

Beilstein J. Nanotechnol. 2019, 10, 1464–1474, doi:10.3762/bjnano.10.145

• the initial homogeneous planar texture of the liquid crystal–carbon nanotubes mixture is disturbed in a threshold manner (Fréedericksz transition). The orientational and concentration distributions of the suspension are studied for different values of the magnetic field strength and segregation

• anisotropy of the diamagnetic susceptibility, this leads to a decrease in the critical fields of magnetic [27][28] and electric [14][16][26][29][30] Fréedericksz transition (a threshold process of changing the orientational structure inside an NLC layer under the action of external fields [31]). Experiments

• , angular, and homeotropic phases [39]: The field hc in Equation 15 corresponds to the Fréedericksz transition field from the initial uniform planar phase to the nonuniform angular one. Equation 16 defines two threshold fields hr±, where hr+ corresponds to the transition from the angular phase to the

Direct observation of oxygen-vacancy formation and structural changes in Bi₂WO₆ nanoflakes induced by electron irradiation

• Hong-long Shi,
• Bin Zou,
• Zi-an Li,
• Min-ting Luo and
• Wen-zhong Wang

Beilstein J. Nanotechnol. 2019, 10, 1434–1442, doi:10.3762/bjnano.10.141

• stronger than a threshold field, which mainly depends on bond strength or electrostatic site potential of atoms in the crystal. Table 2 lists the electrostatic site potentials of Bi2WO6 calculated by using the VESTA software based on the Fourier method [33]. The oxygen atoms labeled “O4” and “O5” (Figure

Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices

• Giulia Lo Dico,
• Bernd Wicklein,
• Lorenzo Lisuzzo,
• Giuseppe Lazzara,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2019, 10, 1303–1315, doi:10.3762/bjnano.10.129

• samples in Table 2). A remarkable value of 2900 S·m−1 is obtained at 5 wt % of carbon nanotubes, while the percolation threshold for electrical conductivity is at 4 wt % MWCNT content. The conductivity values are higher than the values reported previously for sepiolite–nanocarbon–polymer bionanocomposites

• S·m−1 [52]). The electrical percolation threshold of the foams was around 6.5 wt % MWCNT content. The higher value in foams reflects a poorer connectivity between carbon nanoparticles dispersed in the clay–polymer matrix probably due to the high porosity, requiring a larger amount of GNPs/MWCNTs to

• form a conducting network within the matrix of the bionanocomposite. In any case, the percolation threshold is on par or slightly lower than the values for related MWCNT–polymer composites, which are in the range of 4–9 wt % [56][57]. The bionanocomposite sample Film-1 was used to evaluate the

Molecular attachment to a microscope tip: inelastic tunneling, Kondo screening, and thermopower

• Rouzhaji Tuerhong,
• Mauro Boero and
• Jean-Pierre Bucher

Beilstein J. Nanotechnol. 2019, 10, 1243–1250, doi:10.3762/bjnano.10.124

• spectroscopy (IETS) close to the Fermi level. The differential conductance (dI/dV) spectrum (Figure 2e) reveals a prominent sharp peak close to the zero-bias voltage and two side peaks corresponding to step-like increases in the dI/dV signal (labeled ΔG) at threshold voltages |Vth| = 110 ± 5 meV. This is a

• vibration modes of transition-metal phthalocyanines [29][30], the two steps at |Vth| = 110 ± 5 mV are easily assigned to the excitation of the stretching of the Mn–Niso bonds of the MnPc molecule. The conductance step ΔG at the positive threshold voltage of 110 ± 5 mV, corresponds to an increase in the

• function of the gap resistance in Figure 4a, is a very sharp effect and corresponds to a sudden configurational change of the molecule in the STM gap. Simultaneously, a telegraphic noise appears at bias voltages larger than the side-peak threshold, which is often regarded as the signature of an unstable

Green fabrication of lanthanide-doped hydroxide-based phosphors: Y(OH)₃:Eu³⁺ nanoparticles for white light generation

• Tugrul Guner,
• Anilcan Kus,
• Mehmet Ozcan,
• Aziz Genc,
• Hasan Sahin and
• Mustafa M. Demir

Beilstein J. Nanotechnol. 2019, 10, 1200–1210, doi:10.3762/bjnano.10.119

• material systems such as SrTiO3 [53], Zn2GeO4 [54], La(OH)3:Eu3+ and La2O3:Eu3+ [52] in the literature, is associated with fast crystal growth. A possible cause could be the oversaturation of reactant species. When the concentration of reactive species appears to be higher than the threshold (which may

Electroluminescence and current–voltage measurements of single-(In,Ga)N/GaN-nanowire light-emitting diodes in a nanowire ensemble

• David van Treeck,
• Johannes Ledig,
• Gregor Scholz,
• Jonas Lähnemann,
• Mattia Musolino,
• Abbes Tahraoui,
• Oliver Brandt,
• Andreas Waag,
• Henning Riechert and
• Lutz Geelhaar

Beilstein J. Nanotechnol. 2019, 10, 1177–1187, doi:10.3762/bjnano.10.117

• series resistances as well as the threshold voltages of the single NWs. Finally, we analyze the dependence of the external quantum efficiency (EQE) on the current in single-NW LEDs. By comparing the trends for single and ensemble measurements, we estimate the number of active NWs in the ensemble LED

• point most certainly two NWs are contacted, resulting in half the series resistance compared to that of the single-NW measurements C, E, and G. Another parameter that can be extracted from the I–V behavior is the threshold voltage Vth, which is defined as the zero-crossing of the linear fit function of

• the respective I–V curves. As an example, the dashed line shows the linear fit for NW C. The threshold voltages for the different measurements are shown in Table 1. These values are in agreement with the actual turn-on voltage for which the first EL signal was detected. The comparatively high

Fe₃O₄ nanoparticles as a saturable absorber for giant chirped pulse generation

• Ji-Shu Liu,
• Xiao-Hui Li,
• Abdul Qyyum,
• Yi-Xuan Guo,
• Tong Chai,
• Hua Xu and
• Jie Jiang

Beilstein J. Nanotechnol. 2019, 10, 1065–1072, doi:10.3762/bjnano.10.107

• available. In this work, the shortest pulse has been obtained in a fiber ring laser based on FONPs for the first time. The FONP solution is inserted into a fiber adapter to compose a sandwich structure SA without any polymer, which effectively increases the damage threshold. The modulation depth and the

Revisiting semicontinuous silver films as surface-enhanced Raman spectroscopy substrates

• Malwina Liszewska,
• Bogusław Budner,
• Małgorzata Norek,
• Bartłomiej J. Jankiewicz and
• Piotr Nyga

Beilstein J. Nanotechnol. 2019, 10, 1048–1055, doi:10.3762/bjnano.10.105

• through percolated films to almost continuous films. We found that films below the percolation threshold (transition from dielectric-like to metal-like) made of isolated silver structures provided the largest SERS enhancement of 4-aminothiophenol (4-ATP) analyte signals. The substrate closest to the

• percolation threshold has the SERS signal about four times lower than the highest signal sample. Keywords: metal island film; plasmon resonance; semicontinuous silver film; SERS; surface-enhanced Raman spectroscopy; Introduction Noble metal nanostructures exhibit exceptional optical properties. They can

• the percolation threshold. The sample closest to the threshold has a SERS signal about four times lower than for the highest signal case. Experimental Materials Silver deposition material (99.99%) and BK7 glass substrates were purchased from Umicore. For glass substrates cleaning process, we used

Correlation of surface-enhanced Raman scattering (SERS) with the surface density of gold nanoparticles: evaluation of the critical number of SERS tags for a detectable signal

• Vincenzo Amendola

Beilstein J. Nanotechnol. 2019, 10, 1016–1023, doi:10.3762/bjnano.10.102

• same area probed by Raman spectroscopy. In this way, the minimum number of AuNTs required to generate a detectable signal under ordinary experimental conditions can be identified. In addition, a threshold or minimum number of AuNTs within the probed area that can produce a linear response is identified

• the excitation beam. The results highlight the appreciable intensity of the AuNTs, which allows a clear detection of the Raman signal above the noise threshold with a surface density of only 1 tag/µm2 when using an excitation power of only 0.65 mW at 633 nm with a 50× objective and acquisition times

• as short as 1 s. The tag density can be lowered even below 1 tag/µm2 if the acquisition time can be extended to 10 s, but it should be increased to 3 tags/µm2 with a 20× objective under the same excitation conditions. In case of an ultra-low AuNT density, a threshold of the total number of SERS tags

Direct growth of few-layer graphene on AlN-based resonators for high-sensitivity gravimetric biosensors

• Jimena Olivares,
• Teona Mirea,
• Lorena Gordillo-Dagallier,
• Bruno Marco,
• José Miguel Escolano,
• Marta Clement and
• Enrique Iborra

Beilstein J. Nanotechnol. 2019, 10, 975–984, doi:10.3762/bjnano.10.98

• density and number of graphene layers. We noticed that both lowering the C2H2 flow rates and increasing the overall pressure (up to 12 mTorr) leads to a decrease of the D peak. We also observed that no graphene grows when the overall pressure raises above a given threshold (around 20 mTorr). A more

Electronic properties of several two dimensional halides from ab initio calculations

• Mohamed Barhoumi,
• Ali Abboud,
• Lamjed Debbichi,
• Moncef Said,
• Torbjörn Björkman,
• Dario Rocca and
• Sébastien Lebègue

Beilstein J. Nanotechnol. 2019, 10, 823–832, doi:10.3762/bjnano.10.82

• images. Geometries (cell and atom positions) were relaxed with a threshold on forces of 10−6 eV/Å. The phonon dispersion curves of the single layers, as presented in Supporting Information File 1, were determined with the PHONOPY code [39] with a 5 × 5 × 1 supercell using density functional perturbation