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

• mobility and, consequently, graphene conductivity. On the other hand, chemical functionalization of graphene may improve the sensitivity of graphene-based sensors [6]. Therefore, the control of density and types of defects in graphene might be a new way to prepare efficient molecular sensors. Systems

• , carrier mobility. The 2D band energy and FWHM also depend on carrier concentration. However, their changes are significantly lower than those found for the G band FWHM, which will be discussed in the next paragraph [43]. The analysis of graphene G band parameters allows for one to trace how NW substrate

• carrier mobility in N0 and N100 samples (Figure 3b, Figure 3f). The intensity ratio of 2D and G graphene bands in monolayer graphene has been reported to be negatively correlated with carrier concentration [15]. A higher Fermi energy increases the probability of scattering on free carriers, which adds to

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• average size of 34 ± 14 nm. The temperature experiment results showed a higher enhancement with temperature increase. Performed simulation studies revealed a slowdown of the mobility of the water molecules close to the surface of AgNPs. Keywords: Dynamic lattice liquid (DLL) simulations; liquid water

• enhanced by the mobility decrease in the nearest vicinity of the metal nanoparticle and by the increase of the rotational relaxation time and residence time of water molecules surrounding the ion wall in a charged monolayer-protected Au nanoparticle [39]. Assuming that the observed Raman enhancement is

• ) – CASE C; (v) Eb = 19 kJ/mol, Ew = 21.1 kJ/mol (Eb = 0.90Ew) – CASE D. The solvent mobility was calculated as an averaged probability of movement of a water-like element at a given distance (r) from the Ag wall. The Figure 5 presents the results of the DLL simulation. The κ parameter is defined as: and

Boosting of photocatalytic hydrogen evolution via chlorine doping of polymeric carbon nitride

• Malgorzata Aleksandrzak,
• Michalina Kijaczko,
• Wojciech Kukulka,
• Daria Baranowska,
• Martyna Baca,
• Beata Zielinska and
• Ewa Mijowska

Beilstein J. Nanotechnol. 2021, 12, 473–484, doi:10.3762/bjnano.12.38

• with the P atom may promote the mobility of the charge carrier and facilitate the separation of the photogenerated electron–holes [34]. Another research group found that their prepared fluorinated carbon nitride has a photocatalytic activity 20.8 times higher than that of pristine PCN [30]. Wang et al

Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

• Rafal Zuzak,
• Marek Szymonski and
• Szymon Godlewski

Beilstein J. Nanotechnol. 2021, 12, 232–241, doi:10.3762/bjnano.12.19

• atomic-scale defects and our previous experiments with other organic molecules [35], we may expect that single FePc molecules on the surface are trapped at surface defects, although the formation of molecular islands hints at a sufficient mobility of the molecules on the Ge(001):H surface. In a

TiO_x/Pt₃Ti(111) surface-directed formation of electronically responsive supramolecular assemblies of tungsten oxide clusters

• Marco Moors,
• Yun An,
• Agnieszka Kuc and
• Kirill Yu. Monakhov

Beilstein J. Nanotechnol. 2021, 12, 203–212, doi:10.3762/bjnano.12.16

• , respectively. After the annealing at 600 K, hardly any single nanocluster can be found on the surface. In return, the step edges are now highly decorated with clusters, while the terraces are covered by up to 1 nm high and 5 nm wide cluster agglomerations. This indicates a high lateral mobility of the clusters

• STM tip-induced manipulation, resulting in a partial reduction to a W3O8 molecule, up to now just theoretically known. At elevated temperatures, the clusters showed a significantly increased lateral mobility, leading first to cluster agglomerations at 600 K and finally to the formation of larger WO3

Toward graphene textiles in wearable eye tracking systems for human–machine interaction

• Ata Jedari Golparvar and
• Murat Kaya Yapici

Beilstein J. Nanotechnol. 2021, 12, 180–189, doi:10.3762/bjnano.12.14

• people with locked-in syndromes who have extremely limited peripheral mobility but still retain their eye motor coordination [10]. Similarly, basic deliberate eye movements such as saccades (i.e., fast eye movements), fixations (i.e., the duration between two saccades when the gaze is fixated at a point

The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• . In [27], we suggested and verified the assumption that a lower density of a nanoscale compact material, in comparison with ordinary bulk samples, leads to an increase in the probability of formation of an atomic structure with a five-particle symmetry due to the greater diffusion mobility of the

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

• introduced during the epitaxial growth process [1][2][3]. Furthermore, the analysis of the internal polarization of the AlGaN/AlN/GaN heterojunction showed the existence of a 2D electron gas (2DEG), which effectively suppresses the degradation of the carrier mobility caused by the scattering at charge

• impurity centers [4]. This is a widely discussed topic in the field of high electron mobility transistor (HEMT) research [5][6]. In order to further improve the physical properties of a 2DEG and optimize the performance of AlGaN/AlN/GaN-based HEMT devices, piezotronic effects are introduced to adjust the

• the study of the piezotronic effect than nanofilms or bulk materials since the smaller physical size and larger surface-to-volume ratio of 1D NWs yields superior mechanical properties [4][10]. In addition, 1D semiconductor NWs can increase the electron mobility and achieve the confinement of light

Absorption and photoconductivity spectra of amorphous multilayer structures

• Oxana Iaseniuc and
• Mihail Iovu

Beilstein J. Nanotechnol. 2020, 11, 1757–1763, doi:10.3762/bjnano.11.158

• Sn impurities on stationary and transient photoconductivity was demonstrated for amorphous As2Se3Snx thin films [5]. The introduction of Sn in the host material increases the drift mobility and the photosensitivity of the amorphous material. According to 119Sn Mössbauer spectroscopy studies of the

• , Nt is the concentration of traps, e is the electron charge, µ is the drift mobility, ε is the dielectric constant, t = Δ/(kBT) (Δ is the parameter of the trap distribution, kB is the Boltzmann constant, T is the absolute temperature), V is the applied voltage, and d is the sample thickness. The

Direct observation of the Si(110)-(16×2) surface reconstruction by atomic force microscopy

• Tatsuya Yamamoto,
• Ryo Izumi,
• Kazushi Miki,
• Takahiro Yamasaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2020, 11, 1750–1756, doi:10.3762/bjnano.11.157

• high-performance metal–oxide–semiconductor field-effect transistors (p-MOSFETs) [1][2] because the hole mobility of Si(110) is twice that of the other Si planes [3]. For surface science research, Si(110) has been used as a template substrate for self-assembled nanowires [4][5][6], nanomeshes [7], and

PEG/PEI-functionalized single-walled carbon nanotubes as delivery carriers for doxorubicin: synthesis, characterization, and in vitro evaluation

• Shuoye Yang,
• Zhenwei Wang,
• Yahong Ping,
• Yuying Miao,
• Yongmei Xiao,
• Lingbo Qu,
• Lu Zhang,
• Yuansen Hu and
• Jinshui Wang

Beilstein J. Nanotechnol. 2020, 11, 1728–1741, doi:10.3762/bjnano.11.155

• molecules enter cells only by mobility or diffusion, while the individually dispersed nanotubes are more easily internalized by cells via direct penetration and endocytosis [38][43]. This can explain the above results. The fluorescence intensity of CNTs-PEG/DOX and CNTs-PEG-PEI/DOX increases further (Figure

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

• of the tip. Figure 6 also shows the CR frequencies acquired on bulk PnBMA. The curve cannot be fitted with Equation 16. This is due to the low elastic modulus and the higher chain mobility of PnBMA. As a consequence, PnBMA is very compliant and can be deformed plastically even with small loads. Hence

• with high chain mobility, that is, with a glass transition temperature near room temperature. This is the case for PnBMA. Considering the CR frequencies (Figure 6), PnBMA behaves like PS and PMMA at small forces and like glass at large forces. In our measurements, γ does indeed depend on the sample

• fitted directly. Yet, such experiments show also that quantitative measurements on polymer samples with elastic moduli smaller than ca. 1 GPa or with a glass transition temperature close to or lower than room temperature (i.e., with very high chain mobility) are affected by serious artefacts and do not

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• at these sites where the SERS effect occurs. On hBN/Cu(111), the significantly smaller interaction between PTCDA and the hBN surface compared to Cu(111) and a consequently smaller corrugation of the bonding potential lead to a much higher mobility, which allows for a diffusion to the hot spots even

Oxidation of Au/Ag films by oxygen plasma: phase separation and generation of nanoporosity

• Abdel-Aziz El Mel,
• Said A. Mansour,
• Mujaheed Pasha,
• Atef Zekri,
• Janarthanan Ponraj,
• Akshath Shetty and
• Yousef Haik

Beilstein J. Nanotechnol. 2020, 11, 1608–1614, doi:10.3762/bjnano.11.143

• , resulting in a mobility decrease at the surface; and (2) the high porosity of the film which serves as a support for the surface diffusion of silver. The clusters formed during the early stages of the process serve as nucleation sites which grow into larger spheres as the oxidation process evolves. The

• surface, which serves as a substrate for the formation of the oxide phase. The presence of such a high porosity is expected to significantly reduce the silver mobility at the surface, posing difficulties to the formation of a continuous silver oxide layer. The formation of nanoporosity within the alloy

Detecting stable adsorbates of (1S)-camphor on Cu(111) with Bayesian optimization

• Jari Järvi,
• Patrick Rinke and
• Milica Todorović

Beilstein J. Nanotechnol. 2020, 11, 1577–1589, doi:10.3762/bjnano.11.140

• structures by computing the potential energy surface (PES). We can identify stable structures in the minima of the PES and evaluate their mobility via the associated energy barriers. The most stable structure, that is the most probable structure in nature, corresponds to the global minimum of the PES. For

• estimate the mobility of the adsorbates from the energy barriers extracted from the surrogate PES and analyze the electronic structure of each adsorbate. Our results provide insight into the adsorption of complex organic molecules on metallic substrates and pave the way to more complex studies of hybrid

• and mobility via the energy barriers on the PES, and investigate their electronic properties with DFT. Bayesian Optimization Structure Search With the atomic structures and their corresponding energies, BOSS constructs a surrogate model of the PES. We define the atomic structures using chemical

Electrokinetic characterization of synthetic protein nanoparticles

• Daniel F. Quevedo,
• Cody J. Lentz,
• Adriana Coll de Peña,
• Yazmin Hernandez,
• Nahal Habibi,
• Rikako Miki,
• Joerg Lahann and
• Blanca H. Lapizco-Encinas

Beilstein J. Nanotechnol. 2020, 11, 1556–1567, doi:10.3762/bjnano.11.138

• homogeneous SPNPs require a much lower trapping voltage than 50:50 anisotropic SPNPs. All eight particle samples were characterized in terms of their linear and their nonlinear electrophoretic mobility, and in terms of their EEEC. These measurements expand the possibilities to use EEEC to characterize

• mobility was obtained by employing Equation 9 with eEEEC values, since both µEO and were experimentally obtained a priori through particle image velocimetry and current monitoring measurements [59]. Equation 9 and its detailed derivation is included in the Theoretical approach section. The linear and the

• nonlinear EP mobility components are essential for the design of EK particle separation experiments. The present report is a pioneer study that considers nonlinear behavior of PNPs. This is still an evolving theory and, as such, more research regarding this topic is required as stated in three recent review

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• critical factor for this phase transition is the density of charged molecules present on the surface. The planarization and electrostatic interaction of the charged molecules with the substrate can be expected to reduce the mobility of the charged molecules. These charged molecules will in turn restrict

• molecules hinders the mobility of the twisted neutral molecules [38]; therefore, when approximately 30% of the molecules are charged, a transition occurs and the neutral molecules also wet the surface. The conformational change induced by charge transfer leads to the final pinning work function being higher

A wideband cryogenic microwave low-noise amplifier

• Boris I. Ivanov,
• Dmitri I. Volkhin,
• Ilya L. Novikov,
• Dmitri K. Pitsun,
• Dmitri O. Moskalev,
• Ilya A. Rodionov,
• Evgeni Il’ichev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1484–1491, doi:10.3762/bjnano.11.131

• str. 5, Moscow, 105005, Russia Dukhov Automatics Research Institute, (VNIIA), 22 ul. Sushchevskaya, Moscow, Russia, 127055 Leibniz Institute of Photonic Technology, PO Box 100239, D-07702 Jena, Germany 10.3762/bjnano.11.131 Abstract A broadband low-noise four-stage high-electron-mobility transistor

• -electron-mobility transistor (HEMT); HEMT amplifier; microwave cryogenic amplifier; microwave superconducting circuit readout; superconducting qubit readout; Introduction Quantum microwave devices are widely used for different applications ranging from radio astronomy [1][2][3] to quantum information

• of liquid helium [11][12][13][14][15][16] and are, usually, placed at the 4 K stage of dilution refrigerators. These amplifiers can be implemented using two modern semiconductor transistor technologies, that is, high-electron-mobility transistor (HEMT) technology, including GaAs and InP, and SiGe

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS₂ field-effect transistors

• Jakub Jadwiszczak,
• Pierce Maguire,
• Conor P. Cullen,
• Georg S. Duesberg and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

• Technology, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany 10.3762/bjnano.11.117 Abstract Helium ion irradiation is a known method of tuning the electrical conductivity and charge carrier mobility of novel two-dimensional semiconductors. Here, we report a systematic

• improvement of both the carrier mobility in the transistor channel and the electrical conductance of the MoS2, due to doping with ion beam-created sulfur vacancies. Larger areal irradiations introduce a higher concentration of scattering centers, hampering the electrical performance of the device. In addition

• negative gate biases [20][21]. These complex states may also improve the carrier mobility across a given gate bias range by forming stable impurity bands near the conduction band [22]. Some theoretical studies suggest, however, that individual SVs ought to act as electron acceptors in MoS2 [23][24]. As the

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

• successfully prepared from N-doped SnO2 films. Through Al/N co-doping, a p-type SnO2 semiconductor thin film with excellent electrical properties was prepared. The resistivity, hole concentration and hole mobility were 7.1 × 10−3 Ω·cm, 6.24 × 1019 cm−3 and 14.1 cm2·V−1·s−1, respectively [8]. Doping SnO2 with F

Cryogenic low-noise amplifiers for measurements with superconducting detectors

• Ilya L. Novikov,
• Boris I. Ivanov,
• Dmitri V. Ponomarev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1316–1320, doi:10.3762/bjnano.11.115

• mobility transistor (HEMT) technology and SiGe bipolar heterojunction technology (HBT). Low-frequency amplifiers are usually applied as first stage of SQUID readout electronics [11][12] or as the readout of cryogenic bolometers [13]. In both cases the amplifiers have a working temperature of 300 K. Modern

Growth of a self-assembled monolayer decoupled from the substrate: nucleation on-command using buffer layers

• Robby Reynaerts,
• Kunal S. Mali and
• Steven De Feyter

Beilstein J. Nanotechnol. 2020, 11, 1291–1302, doi:10.3762/bjnano.11.113

• anticipated, the mobility of BA-OC14 on the buffer layers was significantly higher than that at the 1-phenyloctane–HOPG interface. It was possible to observe the nucleation, the growth as well as the desorption of molecular domains (see Figure S7 in the Supporting Information File 1) which was otherwise not

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

• electrochemical properties of the original carbon matrix can be significantly improved [27]. The perfect crystalline graphene has an ideal two-dimensional crystal structure composed of a stable regular hexagonal lattice, which has an excellent theoretical specific surface area, increased electron mobility, high

Gas sorption porosimetry for the evaluation of hard carbons as anodes for Li- and Na-ion batteries

• Yuko Matsukawa,
• Fabian Linsenmann,
• Maximilian A. Plass,
• George Hasegawa,
• Katsuro Hayashi and
• Tim-Patrick Fellinger

Beilstein J. Nanotechnol. 2020, 11, 1217–1229, doi:10.3762/bjnano.11.106

• precursors is by one order of magnitude less expensive [7]. LIBs and SIBs have different applications. While LIBs are used as traction batteries in BEVs, in which volumetric energy density is crucial for a long mobility range, SIBs are mainly used for grid energy storage applications due to their lower cost

• only allows for a limited mobility range, therefore, HCs are investigated regarding the potential for higher energy densities. The seasonal and daytime-dependent character of solar and wind energy requires stationary electricity storage for times of light and wind shortage, with a focus on low cost. To

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• ][17][18][19], Ru [20][21], Pt [22][23], SiC [24][25][26], and SiO2 [27][28][29]. Unfortunately, the obtained experimental data showed that the incompatible crystalline structure of the above materials leads to significant suppression of the carrier mobility of graphene [13][30]. It is now assumed that

• nontoxic. It is worth noting that graphene on a hBN substrate was used to fabricate transistor devices with high mobility [35], with the help of which the quantum Hall effect was observed. A heterojunction with two graphene layers [30] and superlattice structures [36][37][38] were also constructed. The