Resonance of graphene nanoribbons doped with nitrogen and boron: a molecular dynamics study

• Ye Wei,
• Haifei Zhan,
• Kang Xia,
• Wendong Zhang,
• Shengbo Sang and
• Yuantong Gu

Beilstein J. Nanotechnol. 2014, 5, 717–725, doi:10.3762/bjnano.5.84

• the resonance of graphene with different dopants, which may benefit their application as resonators. Keywords: dopant; graphene; molecular dynamics simulation; natural frequency; quality factor; resonance; Introduction Graphene has drawn intensive interest since its discovery in 2005 [1]. It has

• bonding energy, such bonds will not exist in doped models. To ensure a reasonable comparison, the sample with a higher density of dopants contains all the dopant positions in the model with a lower doping percentage. To describe the atomic interactions between carbon atoms, the commonly utilised reactive

• -distance C–C interaction in the form of a typical Lennard-Jones (LJ) potential. The last term describes the dihedral-angle preferences in hydrocarbon configurations. For the other atomic interactions induced by the dopant atoms (i.e., C–B, C–N, and B–N), a typical Tersoff potential [26] was adopted. For

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• semiconductors because the special structure of the interlayer galleries of ion-exchangeable semiconductors provides excellent channels for the diffusion of dopant and finally resulted in a uniform distribution of dopant over the whole semiconductor materials. The homogeneous doping leads to a significantly

High activity of Ag-doped Cd_0.1Zn_0.9S photocatalyst prepared by the hydrothermal method for hydrogen production under visible-light irradiation

• Leny Yuliati,
• Melody Kimi and
• Mustaffa Shamsuddin

Beilstein J. Nanotechnol. 2014, 5, 587–595, doi:10.3762/bjnano.5.69

• ], and Sr [17] has been a good attempt to increase the visible-light absorption of the Cd1−xZnxS photocatalyst. The use of Ag species as a good dopant for various types of photocatalysts has been also reported [18][19][20], including its use to modify Cd1−xZnxS [21][22][23]. Cd1−xZnxS modified by Ag2S

• was used as a dopant [9]. There are no diffraction peaks corresponding to Ag or other crystal phases. This could be due to the fact that the content of Ag might be too small to be detected or Ag was well dispersed in Cd0.1Zn0.9S. This result also indicated that no detectable impurity phases existed in

• the prepared samples. The small amount of Ag dopant increased remarkably the intensity of the diffraction peaks compared to the undoped Cd0.1Zn0.9S (Figure 1a,b), which suggests that a small amount of Ag might induce the crystal growth. However, further increase of the Ag dopant did not further

Tensile properties of a boron/nitrogen-doped carbon nanotube–graphene hybrid structure

• Kang Xia,
• Haifei Zhan,
• Ye Wei and
• Yuantong Gu

Beilstein J. Nanotechnol. 2014, 5, 329–336, doi:10.3762/bjnano.5.37

• with different dopants. It is found that with the presence of dopants, the hybrid structures usually exhibit lower yield strength, Young’s modulus, and earlier yielding compared to that of a pristine hybrid structure. For dopant concentrations below 2.5% no significant reduction of Young’s modulus or

• impact of dopant atoms on the mechanical properties of graphene. Huge efforts are still lying ahead especially for the newly synthesized CNT–graphene hybrid structure. Therefore, in this work, we will examine the impact of different densities and species of dopants on the tensile properties of the GNHS

• graphene sheet to fit the armchair (4,4)-CNT with a height of 13.8 Å. Basically, three groups of sample structures have been tested, which include GNHS with nitrogen dopant (GNHS-N), GNHS with boron dopant (GNHS-B), and GNHS with both nitrogen and boron dopants (GNHS-NB). Each group contains six doped

Kelvin probe force microscopy of nanocrystalline TiO₂ photoelectrodes

• Alex Henning,
• Gino Günzburger,
• Res Jöhr,
• Yossi Rosenwaks,
• Biljana Bozic-Weber,
• Catherine E. Housecroft,
• Edwin C. Constable,
• Ernst Meyer and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2013, 4, 418–428, doi:10.3762/bjnano.4.49

• the incident light since the nanoporous TiO2, deposited on top of the FTO-layer, is only about 10 μm thin and transparent to visible light (Eg = 3.2 eV). Due to the high n-dopant density of SnO2:F (ND ~ 1020), it can be approximated to being nearly metallic. Generally, the SnO2:F contact is regarded

Ferromagnetic behaviour of Fe-doped ZnO nanograined films

• Boris B. Straumal,
• Svetlana G. Protasova,
• Andrei A. Mazilkin,
• Thomas Tietze,
• Eberhard Goering,
• Gisela Schütz,
• Petr B. Straumal and
• Brigitte Baretzky

Beilstein J. Nanotechnol. 2013, 4, 361–369, doi:10.3762/bjnano.4.42

• as the minimum possible one for the iron-doped ZnO. In Figure 4 only the synthesis temperature and specific area of GBs are taken into account. However, the saturation magnetization Js of the doped ZnO depends on the dopant concentration in a nontrivial manner (see for example [17]). In the case of

• previously that the texture or the amount of intergranular amorphous phase in the nanograined pure ZnO films drastically influences the FM properties even at the same grain size [68][69][70]. The GB structure also changes with increasing dopant content [71]. Moreover, by varying the synthesis conditions one

A highly pH-sensitive nanowire field-effect transistor based on silicon on insulator

• Denis E. Presnov,
• Sergey V. Amitonov,
• Pavel A. Krutitskii,
• Valentina V. Kolybasova,
• Igor A. Devyatov,
• Vladimir A. Krupenin and
• Igor I. Soloviev

Beilstein J. Nanotechnol. 2013, 4, 330–335, doi:10.3762/bjnano.4.38

• [11][14][15][16] for solving the Poisson–Boltzmann equation do not allows one to clearly demonstrate the behaviour of the studied system in different modes. In our calculations we assumed the absence of charges inside the oxide layer and a uniformity of the dopant density in the NW as in [13

• theoretical limit of 59 mV/pH and is not inferior to VLS-grown nanowires [7][13]. It was shown that the simplified fabrication technology with Schottky barriers in contact regions allows one to avoid processes of doping and dopant activation and has no effect on the NW transport-current fluctuation density

High-resolution electrical and chemical characterization of nm-scale organic and inorganic devices

• Pierre Eyben

Beilstein J. Nanotechnol. 2013, 4, 318–319, doi:10.3762/bjnano.4.35

• information. It is therefore important to develop and improve two- and three-dimensional characterization techniques that can be utilized on both organic and inorganic semiconductors. These techniques should allow determination of the carrier/dopant distribution with an excellent sensitivity and repeatability

A look underneath the SiO₂/4H-SiC interface after N₂O thermal treatments

• Patrick Fiorenza,
• Filippo Giannazzo,
• Lukas K. Swanson,
• Alessia Frazzetto,
• Simona Lorenti,
• Mario S. Alessandrino and
• Fabrizio Roccaforte

Beilstein J. Nanotechnol. 2013, 4, 249–254, doi:10.3762/bjnano.4.26

• (flat and faceted). Both samples were subjected to p-type doping by Al ion implantation and to a subsequent high-temperature (1650 °C) postimplantation annealing for dopant activation. On one sample, the SiC surface was coated by a protective carbon capping layer during the annealing, resulting in a

Functionalization of vertically aligned carbon nanotubes

• Eloise Van Hooijdonk,
• Carla Bittencourt,
• Rony Snyders and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2013, 4, 129–152, doi:10.3762/bjnano.4.14

Diamond nanophotonics

• Katja Beha,
• Helmut Fedder,
• Marco Wolfer,
• Merle C. Becker,
• Petr Siyushev,
• Mohammad Jamali,
• Anton Batalov,
• Christopher Hinz,
• Jakob Hees,
• Lutz Kirste,
• Harald Obloh,
• Etienne Gheeraert,
• Boris Naydenov,
• Ingmar Jakobi,
• Florian Dolde,
• Sébastien Pezzagna,
• Daniel Twittchen,
• Matthew Markham,
• Daniel Dregely,
• Harald Giessen,
• Jan Meijer,
• Fedor Jelezko,
• Christoph E. Nebel,
• Rudolf Bratschitsch,
• Alfred Leitenstorfer and
• Jörg Wrachtrup

Beilstein J. Nanotechnol. 2012, 3, 895–908, doi:10.3762/bjnano.3.100

• MWPECVD. Emphasis was placed on a reproducible dopant addition to the growth process aiming at a targeted in situ incorporation of color centers based on nickel and tungsten impurities. A very promising single-photon-emitting defect for quantum-cryptographic applications is the so-called NE8-center [17

• diamond growth is a crucial step for the in situ synthesis of color centers. A frequently applied method is to expose a solid state source containing the dopant material directly to the reactive plasma [15][19][21]. We also used this approach for the doping of nanodiamond crystals with silicon, which will

• be discussed in section 5.5. A drawback of a solid-state doping source is the limited control over the dopant concentration during growth. To ensure a reproducible doping we studied the applicability of gaseous metal precursors, namely nickelocene Ni(C5H5)2 and tungsten hexacarbonyl W(CO)6, for the

The memory effect of nanoscale memristors investigated by conducting scanning probe microscopy methods

• César Moreno,
• Carmen Munuera,
• Xavier Obradors and
• Carmen Ocal

Beilstein J. Nanotechnol. 2012, 3, 722–730, doi:10.3762/bjnano.3.82

• correlation of device rectification (reset) with the voltage employed to induce each particular state. Analytical simulations by using a nonlinear dopant drift within a memristor device explain the experimental I–V bipolar cycles. Keywords: conductive scanning probe micoscopy; memristor; 3-D modes; resistive

• observed for a particular memristive system helps to classify the nature of the dopant drift inside the memristor. If the generated electric field can be assumed to be small, the linear dopant-drift model can approximate the dynamics of a memristor. However, this model is not valid in our case. During the

• –sample contact is a factor of ~20 larger than that in region of the film closer to the substrate interface [6]. The influence of a nonuniform electric field significantly suppresses the drift of the dopants. Nonlinear dopant drift can be taken into account in the memristor simulation I–V curve by

Plasmonics-based detection of H₂ and CO: discrimination between reducing gases facilitated by material control

• Gnanaprakash Dharmalingam,
• Nicholas A. Joy,
• Benjamin Grisafe and
• Michael A. Carpenter

Beilstein J. Nanotechnol. 2012, 3, 712–721, doi:10.3762/bjnano.3.81

• overcoat has a crucial role in restricting the growth of the Au NPs during long-term high-temperature exposures, and its thickness has a direct impact on the number of oxygen vacancies in the film. The vacancies are introduced into the film through the yttria dopant in zirconia. YSZ is an excellent oxygen

• , and the number of oxygen vacancies that would be formed due to the yttria dopant level. Calculation of the number of oxygen vacancies per square centimeter led to the following numbers for the films: 8.16 × 1015/cm2 for the small-particle sample and the thinner gold sample, 2.04 × 1015/cm2 for the

Nano-structuring, surface and bulk modification with a focused helium ion beam

• Daniel Fox,
• Yanhui Chen,
• Colm C. Faulkner and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2012, 3, 579–585, doi:10.3762/bjnano.3.67

• properties of the surface [18]. Some other applications to date include imaging of chemical variations at high resolution [19], quantitative dopant contrast mapping [20] and imaging of uncoated biological materials [21]. In this work we further investigate the ability of the HIM to modify a material’s

Synthesis and electrical characterization of intrinsic and in situ doped Si nanowires using a novel precursor

• Wolfgang Molnar,
• Alois Lugstein,
• Tomasz Wojcik,
• Peter Pongratz,
• Norbert Auner,
• Christian Bauch and
• Emmerich Bertagnolli

Beilstein J. Nanotechnol. 2012, 3, 564–569, doi:10.3762/bjnano.3.65

• doped NWs appeared to be [112] oriented with a specific resistivity of ρ = 198 mΩ·cm for p-type Si-NWs and ρ = 2.7 mΩ·cm for n-doped Si-NWs, revealing excellent dopant activation. Keywords: chemical vapour deposition; field-effect transistor; oligosilanes; radiation-induced nanostructures; silicon

• of dopant intentionally to the Au catalyst particle [22]. Much more common and effective is to add a gaseous dopant, such as PH3, B2H6 or B(CH3)3, to the precursor gas feed during growth. Thus, for example, p–i–n+-type doped Si-NW heterostructures with a resistivity of a few mΩ·cm have been achieved

• decomposition of the precursor and therefore increases the growth rate. With PCl3 as the dopant, at least 800 °C, 20 sccm H2, and a 2 nm layer of Au were needed to produce epitaxial NWs in considerable quantity. For a more detailed view of the morphology of the intrinsic and doped Si-NWs we performed HRTEM

X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge

• Carla Bittencourt,
• Adam P. Hitchock,
• Xiaoxing Ke,
• Gustaaf Van Tendeloo,
• Chris P. Ewels and
• Peter Guttmann

Beilstein J. Nanotechnol. 2012, 3, 345–350, doi:10.3762/bjnano.3.39

• . The peak at 284.2 eV, very clear in the spectrum of the flat part of the graphene, also exists at about the same intensity relative to the C 1s continuum intensity, in the spectrum of the fold. Schultz et al. [12] assigned this pre-edge structure to dopant-induced states. As we did not observe this in

Effect of the tip state during qPlus noncontact atomic force microscopy of Si(100) at 5 K: Probing the probe

• Adam Sweetman,
• Sam Jarvis,
• Rosanna Danza and
• Philip Moriarty

Beilstein J. Nanotechnol. 2012, 3, 25–32, doi:10.3762/bjnano.3.3

• atomic diameter per scan), and therefore drift is not an issue in the assignment of atomic position. This assignment is confirmed by analysis of other images with similar contrast in which the presence of dopant-related defects [22][28] allows unambiguous identification of true contrast inversion

Magnetic nanoparticles for biomedical NMR-based diagnostics

• Huilin Shao,
• Tae-Jong Yoon,
• Monty Liong,
• Ralph Weissleder and
• Hakho Lee

Beilstein J. Nanotechnol. 2010, 1, 142–154, doi:10.3762/bjnano.1.17

• highest magnetization and r2 value, on account of their electron spin configurations, followed by FeFe2O4, CoFe2O4, and NiFe2O4. More recently, it has been demonstrated that magnetization can be further enhanced via additional Zn2+ dopant control in MnFe2O4 nanoparticles [46]. In addition, nanoparticle