The effect of magneto-crystalline anisotropy on the properties of hard and soft magnetic ferrite nanoparticles

• Hajar Jalili,
• Bagher Aslibeiki,
• Ali Ghotbi Varzaneh and
• Volodymyr A. Chernenko

Beilstein J. Nanotechnol. 2019, 10, 1348–1359, doi:10.3762/bjnano.10.133

• the particles size. In fact, the high surface-to-volume ratio in the smaller nanoparticles leads to an increase of the surface effects such as spin disorder and dead layer on the surface, eventually resulting in a decrease of the magnetization. The thickness of the surface dead layer (t) equaling to t

Alloyed Pt₃M (M = Co, Ni) nanoparticles supported on S- and N-doped carbon nanotubes for the oxygen reduction reaction

• Stéphane Louisia,
• Yohann R. J. Thomas,
• Pierre Lecante,
• Marie Heitzmann,
• M. Rosa Axet,
• Pierre-André Jacques and
• Philippe Serp

Beilstein J. Nanotechnol. 2019, 10, 1251–1269, doi:10.3762/bjnano.10.125

• structure, and the G band (IG) at ≈1580 cm−1, the first-order Raman band of all sp2 carbon materials. The presence of disorder in CNTs can also impact: i) the intensity of other bands, such as the G’ band at ≈2700 cm−1, and ii) the position and shape of the peaks [40]. The G’ band is indicative of long

• treatment on the N-CNTs (besides the reduction of disorder) is to decrease the amount of nitrogen, which decreases from 2.9 to 1.6%. XPS analysis confirmed the bulk analyses and showed that the S-CNT sample also contains a significant amount of surface oxygen groups. The introduction of oxygen may

• discarded. Wide angle X-ray scattering (WAXS) analysis was performed on Pt3Co/N-CNT and Pt3Ni/N-CNTHT (Figure 8). After corrections and taking a Fourier transform of the scattering data, the related pair distribution function (PDF) is well defined, with a low structural disorder. For Pt3Co/N-CNT, the

Quantitative analysis of annealing-induced instabilities of photo-leakage current and negative-bias-illumination-stress in a-InGaZnO thin-film transistors

• Dapeng Wang and
• Mamoru Furuta

Beilstein J. Nanotechnol. 2019, 10, 1125–1130, doi:10.3762/bjnano.10.112

• conduction is insensitive to disorder because the conduction band edge depends on the In s-orbital [1]. However, there is a high density of oxygen-containing trap states (ca. 1020 cm−3) in the region above the valence band [2], which is sensitive to irradiation with light [3]. The typical staggered/coplanar

Concurrent nanoscale surface etching and SnO₂ loading of carbon fibers for vanadium ion redox enhancement

• Jun Maruyama,
• Shohei Maruyama,
• Tomoko Fukuhara,
• Toru Nagaoka and
• Kei Hanafusa

Beilstein J. Nanotechnol. 2019, 10, 985–992, doi:10.3762/bjnano.10.99

• the concentration of the defects and the extent of the structural disorder [21]. The ID/IG value is similar to that of TGP-550Air. The ID/IG value depends on the thermal oxidation temperature and a highly developed D peak and a slight increase in the Am peak intensity were observed in the spectrum for

• thermal oxidation were reflected by the change in nitrogen surface concentration from TGP-CSnPc to TGP-CSnPc-550Air. The high oxygen surface concentration in TGP-CSnPc was attributed to its rough surface due to the structural disorder of the amorphous carbon, which was susceptible to oxidation upon

Improving control of carbide-derived carbon microstructure by immobilization of a transition-metal catalyst within the shell of carbide/carbon core–shell structures

• Teguh Ariyanto,
• Jan Glaesel,
• Andreas Kern,
• Gui-Rong Zhang and
• Bastian J. M. Etzold

Beilstein J. Nanotechnol. 2019, 10, 419–427, doi:10.3762/bjnano.10.41

• contrast to TPO, XRD and TEM, no strong differences in crystallinity of the samples can be observed by using Raman spectroscopy. All spectra are characterized by the presence of two more or less overlapping D- and G-bands centered at ca. 1325 and 1583 cm−1. CDC-Ni0 shows a slightly higher level of disorder

Integration of LaMnO_3+δ films on platinized silicon substrates for resistive switching applications by PI-MOCVD

• Raquel Rodriguez-Lamas,
• Dolors Pla,
• Odette Chaix-Pluchery,
• Benjamin Meunier,
• Fabrice Wilhelm,
• Andrei Rogalev,
• Laetitia Rapenne,
• Xavier Mescot,
• Quentin Rafhay,
• Hervé Roussel,
• Michel Boudard,
• Carmen Jiménez and
• Mónica Burriel

Beilstein J. Nanotechnol. 2019, 10, 389–398, doi:10.3762/bjnano.10.38

• the orthorhombic mode. At higher wavenumbers, a shift can be observed from the Ag and B2g orthorhombic modes centred at 495 and 614 cm−1, respectively, to the broad Jahn–Teller bands characteristic of mixed-valence manganites with Mn3+/Mn4+ charge and orbital disorder [30], i.e., the first one at ca

Effects of post-lithography cleaning on the yield and performance of CVD graphene-based devices

• Eduardo Nery Duarte de Araujo,
• Thiago Alonso Stephan Lacerda de Sousa,
• Luciano de Moura Guimarães and
• Flavio Plentz

Beilstein J. Nanotechnol. 2019, 10, 349–355, doi:10.3762/bjnano.10.34

• polymer are still present. Structural disorder in graphene can be quantified through the ID/IG intensity ratio. For laser excitation with wavelength λL, the characteristic size of well-ordered domains in graphene can be estimated as: which properly applies to La > 4 nm [19][20][21]. According to Figure 4

• graphene. Furthermore, the value of La showed no expressive decrease as the devices fabricated by procedure P2 are cleaned by method C1. However, when the cleaning is performed by methods C2 and C3, the size of well-ordered domains shows a further decrease, which suggests an increase of structural disorder

• holes. Figure 5 shows that graphene conductivity, σ, behaves as a sublinear function of the gate voltage, Vg. This sublinear behavior is associated to a weak-point disorder in graphene, which emerges as a carrier density independent residual resistivity, ρs. The strong disorder and the charged-impurity

Raman study of flash-lamp annealed aqueous Cu₂ZnSnS₄ nanocrystals

• Yevhenii Havryliuk,
• Oleksandr Selyshchev,
• Mykhailo Valakh,
• Alexandra Raevskaya,
• Oleksandr Stroyuk,
• Constance Schmidt,
• Volodymyr Dzhagan and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2019, 10, 222–227, doi:10.3762/bjnano.10.20

• lower frequency values can be cation disorder [10][39], the formation of other polytypes, particularly so-called disordered KS [10][39], stannite [39][41], and wurtzite (WZ) [42][43][44]. Based on the XRD data of our samples [21], we can exclude the WZ phase. Furthermore, the Raman spectra of freshly

• bulk CZTS [10][11]. The discussed “disorder” does not mean, however, the absence of crystallinity, as can be concluded from the sharp phonon spectra (Figure 1). It is rather a certain rearrangement of the cations (and probably anions) in the sublattice that does not deteriorate the overall

Nanoporous water oxidation electrodes with a low loading of laser-deposited Ru/C exhibit enhanced corrosion stability

• Sandra Haschke,
• Dmitrii Pankin,
• Vladimir Mikhailovskii,
• Maïssa K. S. Barr,
• Adriana Both-Engel,
• Alina Manshina and
• Julien Bachmann

Beilstein J. Nanotechnol. 2019, 10, 157–167, doi:10.3762/bjnano.10.15

• -frequency region, the conspicuous maximum at ≈1600 cm−1 is due the stretching vibration of C=C bonds in aromatic or graphitic carbon. The peak at 1224 cm−1 corresponds to stretching vibrations of C–C and C–O single bonds (the ‘disorder’ peak usually found for graphitic material) [56][57][58][59][60][61

Threshold voltage decrease in a thermotropic nematic liquid crystal doped with graphene oxide flakes

• Mateusz Mrukiewicz,
• Krystian Kowiorski,
• Paweł Perkowski,
• Rafał Mazur and
• Małgorzata Djas

Beilstein J. Nanotechnol. 2019, 10, 71–78, doi:10.3762/bjnano.10.7

• aggregates is much more visible for the higher concentration (Figure 3e) than for the lower concentration (Figure 3b). The large aggregates disorder the long-range orientational order and disturb the liquid crystal alignment. According to the classical Michel–Levy interference color chart [38], we observe a

Zn/F-doped tin oxide nanoparticles synthesized by laser pyrolysis: structural and optical properties

• Florian Dumitrache,
• Iuliana P. Morjan,
• Elena Dutu,
• Ion Morjan,
• Claudiu Teodor Fleaca,
• Monica Scarisoreanu,
• Alina Ilie,
• Marius Dumitru,
• Cristian Mihailescu,
• Adriana Smarandache and
• Gabriel Prodan

Beilstein J. Nanotechnol. 2019, 10, 9–21, doi:10.3762/bjnano.10.2

• qualitative information via phononic behavior regarding the crystalline nature of materials, is a useful tool for investigating disorder in oxide materials. Figure 4a presents a typical room temperature Raman spectra of as-synthesized F or Zn/F-doped SnO2 nanopowders. The Raman spectra analyzed in this work

• (Figure 4b) a direct dependence of the mode frequency with XPS Zn content detected on the nanoparticle surface. This shifting correlated with the B2g Raman mode area increase indicates nanoparticle surface disorder induced by F attachment. S1 and S2 bands appear as a disorder activation consequence [25

• ] inferred by F, Zn and nanocrystallite size. When the F concentration is high (without Zn doping) the disorder is considered to be surface induced, while for a sample with a high Zn concentration (EDX – 3.74 atom %), ZTO0.44, the disorder is volume generated, along with a depreciation in the crystalline

Disorder in H⁺-irradiated HOPG: effect of impinging energy and dose on Raman D-band splitting and surface topography

• Lisandro Venosta,
• Noelia Bajales,
• Sergio Suárez and
• Paula G. Bercoff

Beilstein J. Nanotechnol. 2018, 9, 2708–2717, doi:10.3762/bjnano.9.253

• . 8400 San Carlos de Bariloche, Argentina 10.3762/bjnano.9.253 Abstract Disorder was induced in pristine highly oriented pyrolytic graphite (HOPG) by irradiation with H+ ions with energies of 0.4 MeV and 1 MeV, and doses of 1014 ions/cm2 and 1016 ions/cm2. Raman spectroscopy was used as the main

• engineering in carbon-based materials. Keywords: disorder; highly oriented pyrolytic graphite (HOPG); ion–solid interactions; Raman spectroscopy; topography; Introduction The development of novel methods to control the properties of carbon-based materials by introducing disorder is currently a subject of

• interest for many nanotechnological applications [1][2][3]. The identification of particle-induced disorder in the sp2 carbon network [3][4][5][6][7], such as the creation and aggregation of defects and/or impurities, has been mainly conducted by using Raman spectroscopy as a fast and non-destructive tool

Block copolymers for designing nanostructured porous coatings

• Roberto Nisticò

Beilstein J. Nanotechnol. 2018, 9, 2332–2344, doi:10.3762/bjnano.9.218

• –disorder transition at a certain value of χN [43]. In detail, the Flory–Huggins model relies on the thermodynamics of polymer solutions by considering the Gibbs free energy for mixing polymer with solvents. According to the Flory–Huggins theory, to calculate the Flory–Huggins interaction parameter, it must

• polymeric systems enhances the disorder degree within the polymeric chains since it mediates also nonfavorable interactions within the polymeric chains, working as plasticizers (affecting also the glass transition temperature value). When the evaporation phenomenon takes place at the film surface

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• suppressed lattice disorder of this HP results in a low density of traps and sub-bandgap states reflecting in a relatively small Eg–Voc loss of 0.45 eV [70]. The bandgap of alloyed FASnxPb1−xI3 HPs was found to vary in an unexpected way, that is, decreasing upon the introduction of Sn from ≈1.5 eV for MAPI

• characteristic Urbach energy of ≈60 meV, indicating a substantial level of structural and energetic disorder. Due to the disorder, planar inverted solar cells based on amorphous MA3Sb2I9 showed low photocurrent densities, however, with a relatively high open-circuit voltage (≈890 meV) and a decent fill factor

Influence of the thickness of an antiferromagnetic IrMn layer on the static and dynamic magnetization of weakly coupled CoFeB/IrMn/CoFeB trilayers

• Deepika Jhajhria,
• Dinesh K. Pandya and
• Sujeet Chaudhary

Beilstein J. Nanotechnol. 2018, 9, 2198–2208, doi:10.3762/bjnano.9.206

• in the magnitude and direction of both magnetization and magnetic anisotropy. It could be associated with the magnetic disorder created due to the large interfacial roughness of IrMn at higher tIrMn, which is also supported well by the XRR fitting results. On the other hand, the extrinsic

Interaction-induced zero-energy pinning and quantum dot formation in Majorana nanowires

• Samuel D. Escribano,
• Alfredo Levy Yeyati and
• Elsa Prada

Beilstein J. Nanotechnol. 2018, 9, 2171–2180, doi:10.3762/bjnano.9.203

• -based quantum computing devices [6][7][8][9]. Progress in fabrication techniques has allowed to induce a hard superconducting gap in InAs [10] or InSb [11] nanowires with epitaxially deposited Al layer. Moreover, last-generation devices exhibit a very low degree of disorder, which allows them to almost

• and the unavoidable presence of disorder [38]. If this is the case, it is then characterized by a finite effective dielectric permittivity which depends on the SC shell width as well as its composition, as we show in Section 1 of Supporting Information File 1. Some experiments [39] have reported that

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• -bandgap region [53][54][55][56] including band tails that yield the Urbach energy as a measure of disorder as well as the detection of (optically active) defects in the band gap which can act as recombination centers in a solar cell. The Sb-TU process shows a slight increase in uncovered substrate area

Defect formation in multiwalled carbon nanotubes under low-energy He and Ne ion irradiation

• Santhana Eswara,
• Jean-Nicolas Audinot,
• Brahime El Adib,
• Maël Guennou,
• Tom Wirtz and
• Patrick Philipp

Beilstein J. Nanotechnol. 2018, 9, 1951–1963, doi:10.3762/bjnano.9.186

• show that ion irradiation with incidence angles closer to the surface normal favours the formation of double and multiple vacancies and in-plane disorder while more grazing incidence leads mainly to single vacancies and substitution, the latter being limited to chemical species reacting with carbon [9

• in the sample. Depending on the sample a fourth peak due to intercalated graphite compounds and increasing disorder produced by functionalization and strain can appear in the region of 1617–1625 cm−1 [1]. Further information on defects can be obtained by the intensity of optical absorbance which is

• quite a large amount of disorder is present in our initial samples. For He+ irradiation at 1017 ions/cm2 two different spectra have been obtained. The spectra with D and G band has been obtained on suspended nanotubes while the spectra with only a broad G band has been recorded on a part of the sample

Synthesis of carbon nanowalls from a single-source metal-organic precursor

• André Giese,
• Sebastian Schipporeit,
• Volker Buck and
• Nicolas Wöhrl

Beilstein J. Nanotechnol. 2018, 9, 1895–1905, doi:10.3762/bjnano.9.181

• to measure the structure of the carbon bonds in the materials. In this work the method is used to determine the sp2/sp3 ratio, the disorder of the carbon structures [29][30] and to get spectroscopic fingerprints for the different structures described before. The Raman spectra in this paper are

SO₂ gas adsorption on carbon nanomaterials: a comparative study

• Deepu J. Babu,
• Divya Puthusseri,
• Frank G. Kühl,
• Sherif Okeil,
• Michael Bruns,
• Manfred Hampe and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 1782–1792, doi:10.3762/bjnano.9.169

• -graphene layers [18]. With this morphology it represents a typological carbon adsorbent with extended structural disorder. Graphene oxide (GO) has a 2D layered structure as shown schematically in Figure 1b. The starting material for the synthesis of GO is graphite, the oxidation of which introduces oxygen

• proportional to the presence of defects or disorder in the material and is strongly dependent on the laser excitation energy [32]. The 2D band for sp2-hybridized carbon materials is found between 2500 and 2800 cm−1 and is a double-resonance two-phonon process [33]. The 2D band intensity is found to be

• indicating maximum disorder in the structure. The N2 adsorption isotherms at 77 K of the six adsorbents are plotted in Figure 4a. The predominantly microporous nature of Norit R1 Extra is evident from the Langmuir-type adsorption isotherm (type I). The observed steep adsorption at low relative pressures is

A zero-dimensional topologically nontrivial state in a superconducting quantum dot

• Pasquale Marra,
• Alessandro Braggio and
• Roberta Citro

Beilstein J. Nanotechnol. 2018, 9, 1705–1714, doi:10.3762/bjnano.9.162

• topological invariant. These signatures are topologically robust against small perturbations, such as disorder. This means that these discontinuities and the associated zero-energy modes cannot be removed by the presence of, e.g., disorder or interactions, if these perturbations are small compared to the

Josephson effect in junctions of conventional and topological superconductors

• Alex Zazunov,
• Albert Iks,
• Miguel Alvarado,
• Alfredo Levy Yeyati and
• Reinhold Egger

Beilstein J. Nanotechnol. 2018, 9, 1659–1676, doi:10.3762/bjnano.9.158

• reported below also apply to those settings. Available materials are often of sufficiently high quality to meet the conditions for ballistic transport, and we will therefore neglect disorder effects. In view of the large amount of published theoretical works on the Josephson effect in such systems, let us

Interaction-tailored organization of large-area colloidal assemblies

• Silvia Rizzato,
• Elisabetta Primiceri,
• Anna Grazia Monteduro,
• Adriano Colombelli,
• Angelo Leo,
• Maria Grazia Manera,
• Roberto Rella and
• Giuseppe Maruccio

Beilstein J. Nanotechnol. 2018, 9, 1582–1593, doi:10.3762/bjnano.9.150

• lateral capillary forces tend to induce aggregation and disorder. Nevertheless, we were able to control the surface coverage by tuning the absorption time in order to achieve a long range order. Notably, we showed how this method can be easily transferred for use with different materials to produce large

Robust topological phase in proximitized core–shell nanowires coupled to multiple superconductors

• Tudor D. Stanescu,
• Anna Sitek and
• Andrei Manolescu

Beilstein J. Nanotechnol. 2018, 9, 1512–1526, doi:10.3762/bjnano.9.142

• topological character of these modes endows them with robustness against perturbations that do not close the superconductor gap, e.g., weak interactions, wire bending, a certain amount of disorder, etc. The most straightforward experimental signature of a Majorana mode is a zero-bias conductance peak that is

• satisfying this condition is manifest in regimes characterized by small topological gaps, as δE and ΔE become comparable in the gapless superconductor limit. Effects of disorder Another element that can compromise the topological protection of the Majorana subspace is the presence of disorder. Generically

• , disorder induces low-energy sub-gap states, thus reducing ΔE[46][47][48][49][50]. The effect of potential disorder on a topological phase realized in a triangular wire is illustrated in Figure 12. Panel (A) shows the position dependence (along the wire) of a typical disorder potential Vdis(x) considered in

Disorder-induced suppression of the zero-bias conductance peak splitting in topological superconducting nanowires

• Jun-Tong Ren,
• Hai-Feng Lü,
• Sha-Sha Ke,
• Yong Guo and
• Huai-Wu Zhang

Beilstein J. Nanotechnol. 2018, 9, 1358–1369, doi:10.3762/bjnano.9.128

• -Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China 10.3762/bjnano.9.128 Abstract We investigate the effect of three types of intrinsic disorder, including that in pairing energy, chemical potential, and hopping amplitude, on the transport properties through the superconducting nanowires

• with Majorana bound states (MBSs). The conductance and the noise Fano factor are calculated based on a tight-binding model by adopting a non-equilibrium Green’s function method. It is found that the disorder can effectively lead to a reduction in the conductance peak spacings and significantly suppress

• the peak height. Remarkably, for a longer nanowire, the zero-bias peak could be reproduced by weak disorder for a finite Majorana energy splitting. It is interesting that the shot noise provides a signature to discriminate whether the zero-bias peak is induced by Majorana zero mode or disorder. For