Synthesis and applications of carbon nanomaterials for energy generation and storage

• Marco Notarianni,
• Jinzhang Liu,
• Kristy Vernon and
• Nunzio Motta

Beilstein J. Nanotechnol. 2016, 7, 149–196, doi:10.3762/bjnano.7.17

• also be tuned for different electronic applications [74][75]. Most of these extraordinary properties, in particular the electrical and electronic ones, are attributed to the unique band structure that this material has, which was first calculated in 1947 by P. R. Wallace [76]. The valence band, formed

Large area scanning probe microscope in ultra-high vacuum demonstrated for electrostatic force measurements on high-voltage devices

• Urs Gysin,
• Thilo Glatzel,
• Thomas Schmölzer,
• Adolf Schöner,
• Sergey Reshanov,
• Holger Bartolf and
• Ernst Meyer

Beilstein J. Nanotechnol. 2015, 6, 2485–2497, doi:10.3762/bjnano.6.258

• used to evaluate measured surface potentials to get at least surface relevant information. Figure 9c shows a sketch describing the used band structure and the surface effect. However, such effects are not only limited to surfaces but may also occur at interfaces impacting device properties. Assuming

High I_on/I_off current ratio graphene field effect transistor: the role of line defect

• Mohammad Hadi Tajarrod and
• Hassan Rasooli Saghai

Beilstein J. Nanotechnol. 2015, 6, 2062–2068, doi:10.3762/bjnano.6.210

• along the edge of zigzag nanoribbons. There are also studies on the line defects in armchair nanoribbons [16][17]. The research into divacancies and ELD in armchair nanoribbons shows that the presence of divacancy defects has significant impacts on the band structure and electronic transport properties

• electrical structure of the transistor channel, which conformed to the first-principles calculations used to describe the electronic band structure of ELD-AGNRs [19][20]. The Hamiltonian computation in this system was separated into AGNR (HA), line defect (HD) and coupling between AGNR and the defect (HC

• defect reduces the paths of conducting channels, making larger effective transport gaps. However, with the reduction of paths, the mobility and carrier density at higher energies is extremely reduced. Figure 1c shows the band structure of ideal and defect AGNR. Compared to the ideal AGNR, the band gap of

Simulation of thermal stress and buckling instability in Si/Ge and Ge/Si core/shell nanowires

• Suvankar Das,
• Amitava Moitra,
• Mishreyee Bhattacharya and
• Amlan Dutta

Beilstein J. Nanotechnol. 2015, 6, 1970–1977, doi:10.3762/bjnano.6.201

• ], it is prohibitively difficult to experimentally measure the thermal load on ultrathin CSNWs. The effect of thermal stress on the performance of the device is again two-fold. The mechanical load would alter its electronic band structure and charge carrier mobility [11][12][13], which is particularly

Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

• Xiaoxing Ke,
• Carla Bittencourt and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2015, 6, 1541–1557, doi:10.3762/bjnano.6.158

• the low-loss or valence region of an EELS spectrum (<50 eV) allows one to study the band structure and in particular the dielectric function of a material. In addition to the collective electron excitation modes marked by characteristic plasmon peaks, the joint density of states above the Fermi level

Current–voltage characteristics of manganite–titanite perovskite junctions

• Benedikt Ifland,
• Patrick Peretzki,
• Birte Kressdorf,
• Philipp Saring,
• Andreas Kelling,
• Michael Seibt and
• Christian Jooss

Beilstein J. Nanotechnol. 2015, 6, 1467–1484, doi:10.3762/bjnano.6.152

• electrostatic potential is generated, which modifies the band structure at the interface. The modified interfacial band structure is successfully described by band bending of more or less rigid electron bands. In heterojunctions, materials with different bandgaps meet at the interface. In addition to band

• bending, this leads to sharp discontinuities of the band structure at the interface and is modelled in the framework of a sharp junction [30]. In many perovskite oxides, the band structure is determined to a large degree by the correlation interactions [31]. Since these correlations strongly depend on the

• variation of the correlation interactions and is quite successfully applied to the near-equilibrium interfacial band structure of oxide junctions [22] (see Figure 4 later in this article). An additional important difference compared to conventional semiconductors is the small electronic bandwidth of the

Electron and heat transport in porphyrin-based single-molecule transistors with electro-burnt graphene electrodes

• Hatef Sadeghi,
• Sara Sangtarash and
• Colin J. Lambert

Beilstein J. Nanotechnol. 2015, 6, 1413–1420, doi:10.3762/bjnano.6.146

• of the ribbon. It is apparent that the up-spin is mostly located toward the edges in contrast with the down-spins, which are delocalized over the EBG. The band structure of the electrode is bent in the vicinity of the k point due to the edge states associated with the oxygen atoms (Figure 3b). Due to

• Ry. The geometry optimization for each structure was performed for forces less than 200 meV/Å. The local density of state calculation was performed with a polarized configuration and at zero (electronic) temperature. For the band structure calculation, the EBG electrode was sampled by a 1 × 1 × 500

• , resulting in mixed AA and AB stacking with graphene. a) HOMO−1, b) HOMO, c) LUMO and d) LUMO+1 state iso-surfaces. Molecular and electronic structure of the EBG electrodes. a) Molecular orbital iso-surfaces, b) band structure of EBG electrodes, c) density of states and number of open channels in the EBG

High photocatalytic activity of V-doped SrTiO₃ porous nanofibers produced from a combined electrospinning and thermal diffusion process

• Panpan Jing,
• Wei Lan,
• Qing Su and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 1281–1286, doi:10.3762/bjnano.6.132

• ]. Although a promising photocatalytic candidate, the catalytic activity of SrTiO3 is still heavily influenced by its considerably large band gap of ≈3.25 eV and high dielectric permittivity [14]. The calculated band structure of SrTiO3 shows that the top of the valence band (VB) and the bottom of the

• unoccupied conduction band (CB) are composed of the O 2p and Ti 3d-t2g states, respectively [15]. Due to the small contribution of Sr to the orbital characteristics of the conduction band, the energy difference between the O 2p and Ti 3d states mainly causes the band structure and insulation characteristic

Electronic interaction in composites of a conjugated polymer and carbon nanotubes: first-principles calculation and photophysical approaches

• Florian Massuyeau,
• Jany Wéry,
• Jean-Luc Duvail,
• Serge Lefrant,
• Abu Yaya,
• Chris Ewels and
• Eric Faulques

Beilstein J. Nanotechnol. 2015, 6, 1138–1144, doi:10.3762/bjnano.6.115

• unaffected by the interaction. The band structure around the Fermi level remains the same suggesting negligible energy coupling between the two systems in this energy range.However, the semiconducting (7,0) tube shows large coupling between the PPV state near the Fermi level and the NT conduction band state

A versatile strategy towards non-covalent functionalization of graphene by surface-confined supramolecular self-assembly of Janus tectons

• Ping Du,
• David Bléger,
• Fabrice Charra,
• Vincent Bouchiat,
• David Kreher,
• Fabrice Mathevet and
• André-Jean Attias

Beilstein J. Nanotechnol. 2015, 6, 632–639, doi:10.3762/bjnano.6.64

• be applied to impose a super-period in the graphene atomic lattice. This new method allows the band and sub-band structure to be finely tuned for innovative two-dimensional (2D) semiconductor junctions [8]. However, the controlled positioning and organization of functional molecules into self

Novel ZnO:Ag nanocomposites induce significant oxidative stress in human fibroblast malignant melanoma (Ht144) cells

• Syeda Arooj,
• Samina Nazir,
• Akhtar Nadhman,
• Nafees Ahmad,
• Bakhtiar Muhammad,
• Ishaq Ahmad,
• Kehkashan Mazhar and
• Rashda Abbasi

Beilstein J. Nanotechnol. 2015, 6, 570–582, doi:10.3762/bjnano.6.59

• , 10, 20, and 30% Ag). Silver resulted in a band structure in visible region in all the ZnO:Ag nanocomposites (Figure 3c). Screening of NPs for cytotoxicity The ZnO:Ag nanocomposites were screened for cytotoxicity against two cell lines, HT144 (human malignant melanoma) and HCEC (normal cell line). The

Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires

• Alberto Milani,
• Matteo Tommasini,
• Valeria Russo,
• Andrea Li Bassi,
• Andrea Lucotti,
• Franco Cataldo and
• Carlo S. Casari

Beilstein J. Nanotechnol. 2015, 6, 480–491, doi:10.3762/bjnano.6.49

• Hirsch [1]. Such structures are 2D carbon layers where sp2 rings form a network through sp, linear connections. For some of these systems, peculiar properties are expected such as the existence of Dirac cones in the electronic band structure and extremely high electron mobility [86]. Schematic structures

Fundamental edge broadening effects during focused electron beam induced nanosynthesis

• Roland Schmied,
• Jason D. Fowlkes,
• Robert Winkler,
• Phillip D. Rack and
• Harald Plank

Beilstein J. Nanotechnol. 2015, 6, 462–471, doi:10.3762/bjnano.6.47

• associated surface potential gets increasingly dominated by the SiO2 substrate underneath and finally approaches the same value. As KFM gives insight into the electronic band structure, the distinct potential of the outer halo indicates different chemistries and/or functional properties compared to the

Electrical contacts to individual SWCNTs: A review

• Wei Liu,
• Christofer Hierold and
• Miroslav Haluska

Beilstein J. Nanotechnol. 2014, 5, 2202–2215, doi:10.3762/bjnano.5.229

• shown in Figure 1b), MIGS cause a dipole ring instead of a dipole sheet at the metal–SWCNT interface, which only locally influences the band structures of SWCNTs within a few nanometers (Figure 2a) [14]. In contrast, for the planar contact, the dipole sheet affects the semiconductor band structure over

Two-dimensional and tubular structures of misfit compounds: Structural and electronic properties

• Tommy Lorenz,
• Jan-Ole Joswig and
• Gotthard Seifert

Beilstein J. Nanotechnol. 2014, 5, 2171–2178, doi:10.3762/bjnano.5.226

• on the number of PbSe sublayers in one unit cell of the misfit compound has been investigated (varying m in the sum formula) with the result that the interlayer charge transfer increases with increasing m. Another theoretical work [37] analysed the band structure of (SnS)1.17NbS2 by using a ratio of

Electronic and electrochemical doping of graphene by surface adsorbates

• Hugo Pinto and
• Alexander Markevich

Beilstein J. Nanotechnol. 2014, 5, 1842–1848, doi:10.3762/bjnano.5.195

• experimental results, DFT calculations have shown that K atoms act as electron donors [25][26][27][28]. Electronic band structure calculations show that adsorption of a K atom on graphene results in the shift of the Fermi level above the Dirac point, indicating the n-type doping of graphene, Figure 3a

• wavefunctions of electronic levels marked A and B in the electronic band structure of K on top of graphene. The wavefunction of the level marked A is localized on the K atom while the wavefunction of the highest occupied level, marked B, is delocalised over the graphene layer. These results confirm that charge

• to negative gate voltages indicates an increase of n-type doping with increasing exposure to K atoms. The change in the slope of the curves suggest a reduction of the mobility of the charge carriers. Reprinted with permission from [29]. Copyright 2008 Nature Publishing Group. a) Electronic band

Controlling the optical and structural properties of ZnS–AgInS₂ nanocrystals by using a photo-induced process

• Takashi Yatsui,
• Fumihiro Morigaki and
• Tadashi Kawazoe

Beilstein J. Nanotechnol. 2014, 5, 1767–1773, doi:10.3762/bjnano.5.187

• an incident photon and the band structure of a ZAIS nanocrystal is shown in the left panel. As growth proceeds, the defect levels disappear, resulting in the high-quality nanocrystal at the end (right panel). (b) Controlling the size of a nanocrystal. The relationship between the energy of an

• incident photon and the band structure of a ZAIS nanocrystal is shown in the left panel. As growth proceeds, the size of the nanocrystal increases and the band gap energy decreases below the energy of the incident photon. Electron–hole pairs are then excited and trigger an oxidation–reduction reaction in

Quasi-1D physics in metal-organic frameworks: MIL-47(V) from first principles

• Danny E. P. Vanpoucke,
• Jan W. Jaeken,
• Stijn De Baerdemacker,
• Kurt Lejaeghere and
• Veronique Van Speybroeck

Beilstein J. Nanotechnol. 2014, 5, 1738–1748, doi:10.3762/bjnano.5.184

• dispersion along the the direction of the VO6 chains, similar as for other quasi-1D materials. Keywords: band structure; density functional theory (DFT); low-dimensional electronics; metal-organic frameworks (MOFs); MIL-47; Introduction Metal-organic frameworks (MOFs) present a class of materials located

• on the geometric and electronic structure is investigated: equilibrium structure, energy, bulk modulus and band structure. Also the transition pressure for the large-pore-to-narrow-pore phase transition is estimated, and inter- and intra-chain coupling constants are calculated. Computational details

• × 9 k-points, and the band structure was calculated along the edges of the first Brillouin zone (cf. Figure 1b). The atomic charges in the systems are calculated by using the Hirshfeld-I approach [67][68] as implemented in our in-house-developed code HIVE [69][70][71]. The atom-centered spherical

Numerical investigation of the effect of substrate surface roughness on the performance of zigzag graphene nanoribbon field effect transistors symmetrically doped with BN

• Majid Sanaeepur,
• Arash Yazdanpanah Goharrizi and
• Mohammad Javad Sharifi

Beilstein J. Nanotechnol. 2014, 5, 1569–1574, doi:10.3762/bjnano.5.168

• electronic properties of B–C–N nanostructures and their application in electronic devices have been extensively studied [20][21][22][23][24]. It is shown that a gap can be opened in the GNR band structure by doping with BN [25][26]. This band gap is attributed to the broken symmetry of the graphene sub

Sublattice asymmetry of impurity doping in graphene: A review

• James A. Lawlor and
• Mauro S. Ferreira

Beilstein J. Nanotechnol. 2014, 5, 1210–1217, doi:10.3762/bjnano.5.133

• other novel devices [1][2][3]. One of the main problems with using regular graphene for such applications is the absence of a band gap in the electronic band structure [4], and as a result any field effect transistors (FETs) made using the material (so-called GFETs) would be unable to be switched off

• , comes from matching tight binding and DFT band structure results, a method which is known to systematically underestimate such band gaps. Nevertheless, the band gap obtained can be expected to be much below that required for a GFET device. In-depth DFT calculations by Hou et al. [44] found that the

DFT study of binding and electron transfer from colorless aromatic pollutants to a TiO₂ nanocluster: Application to photocatalytic degradation under visible light irradiation

• Corneliu I. Oprea,
• Petre Panait and
• Mihai A. Gîrţu

Beilstein J. Nanotechnol. 2014, 5, 1016–1030, doi:10.3762/bjnano.5.115

• UV radiation, a fact that limits the efficiency and keeps the costs of the photocatalytic degradation of environmental pollutants high. To be used under visible light irradiation, in the range of wavelengths where the solar spectrum has its maximum, the electronic band structure of the photocatalyst

Functionalized nanostructures for enhanced photocatalytic performance under solar light

• Liejin Guo,
• Dengwei Jing,
• Maochang Liu,
• Yubin Chen,
• Shaohua Shen,
• Jinwen Shi and
• Kai Zhang

Beilstein J. Nanotechnol. 2014, 5, 994–1004, doi:10.3762/bjnano.5.113

• photon by the band gap of semiconductor materials (Figure 1). Upon photon excitation, the photogenerated charges move to the surface of semiconductor particles where photocatalytic reactions occur. Consequently, the efficiency of photocatalytic water splitting is closely affected by the band structure of

• and atom ratios, leading to a deviation of their band structure from their bulk counterpart. Consequently, some crystal facets have shown higher activity than other facets for many photocatalyst during a certain photocatalytic reaction [35][36][37]. Jang et al. found that ZnO nanoplates with a

• change of the dipole moments of the lattice. Such a built-in electrostatic field is obviously favorable for an efficient charge separation and hence leads to enhanced photocatalytic activity. Combined control of band structure and morphology In principle, a semiconductor photocatalyst should meet at

Growth and characterization of CNT–TiO₂ heterostructures

• Yucheng Zhang,
• Ivo Utke,
• Johann Michler,
• Gabriele Ilari,
• Marta D. Rossell and
• Rolf Erni

Beilstein J. Nanotechnol. 2014, 5, 946–955, doi:10.3762/bjnano.5.108

• outer shells, i.e., excitations from the valence band to the conduction band. Hence, the low-loss signal contains information about the band structure of the specimen, and has been used to determine the band gaps of semiconductors [41]. Based on a dielectric model, the dielectric function can be

Biomolecule-assisted synthesis of carbon nitride and sulfur-doped carbon nitride heterojunction nanosheets: An efficient heterojunction photocatalyst for photoelectrochemical applications

• Hua Bing Tao,
• Hong Bin Yang,
• Jiazang Chen,
• Jianwei Miao and
• Bin Liu

Beilstein J. Nanotechnol. 2014, 5, 770–777, doi:10.3762/bjnano.5.89

• eV than for that at 168.2 eV suggests that the replacement of the secondary nitrogen with sulfur in CN is more favorable. The effects of sulfur doping on the optical and energy band structure were investigated by UV–vis absorption and Mott–Schottky measurements. Figure 2a shows the UV–vis diffuse

• ). This type-II band alignment means that once CN and CNS are electronically coupled, a well-matched band structure for charge separation will be formed. In this case, the photogenerated electrons are transferred from CN to CNS, while the photogenerated holes are transferred from CNS to CN, leading to an

An analytical approach to evaluate the performance of graphene and carbon nanotubes for NH₃ gas sensor applications

• Elnaz Akbari,
• Vijay K. Arora,
• Aria Enzevaee,
• Mohamad. T. Ahmadi,
• Mehdi Saeidmanesh,
• Mohsen Khaledian,
• Hediyeh Karimi and
• Rubiyah Yusof

Beilstein J. Nanotechnol. 2014, 5, 726–734, doi:10.3762/bjnano.5.85

• ), as well as various semi-conductive nanowires and nanotubes [10][11]. Arora, Tan, and Gupta [12] have studied the carrier statistics of graphene and response of carriers to high electric fields. Arora and Bhattacharyya [13] have combined the carrier statistics of CNTs and discussed the band structure

• overlap energy. For the first band gap energy we can simply write EG = (2aC-C·t/d) = 0.8 eV·nm/d (nm). In addition, since the band structure is parabolic near the k = 0 points, we can write for the energy: where is the reduced Planck’s constant, kx represents the longitudinal wave vector component along

• applications in variety of sensors because of dangling π-bonds that can react with chemical elements. In spite of their excellent features, carbon nanotubes (CNTs) and graphene have not been fully exploited in the development of the nanoelectronic industry mainly because of poor understanding of the band