Clays enhanced with niobium: potential in wastewater treatment and reuse as pigment with antibacterial activity

• Silvia Jaerger,
• Patricia Appelt,
• Mario Antônio Alves da Cunha,
• Fabián Ccahuana Ayma,
• Ricardo Schneider,
• Carla Bittencourt and
• Fauze Jacó Anaissi

Beilstein J. Nanotechnol. 2025, 16, 141–154, doi:10.3762/bjnano.16.13

• /bjnano.16.13 Abstract Bentonite clay sourced from the Guarapuava region, Brazil, was modified with niobium oxide (BEOx) and niobium phosphate (BEPh) to act as an adsorbent and photocatalyst in the remediation of wastewater containing methylene blue (MB) dye. Additionally, colored materials were evaluated

• for their potential as antibacterial hybrid pigments. The bentonite clay modified with niobium was prepared by a solution containing swelling clay mixed with niobium oxide (NbOx) and niobium phosphate (NbPh) in a water solution; after that, the suspension was calcinated. X-ray diffractometry, X-ray

• photoelectron spectroscopy, and laser-induced breakdown spectroscopy assessed the modifications induced by the incorporation of niobium compounds into the clay, confirming the presence of niobium in the bentonite clay. Following characterization, the BEOx and BEPh samples were used as adsorbents or

Design, fabrication, and characterization of kinetic-inductive force sensors for scanning probe applications

• August K. Roos,
• Ermes Scarano,
• Elisabet K. Arvidsson,
• Erik Holmgren and
• David B. Haviland

Beilstein J. Nanotechnol. 2024, 15, 242–255, doi:10.3762/bjnano.15.23

• kinetic inductance also comes with intrinsic nonlinearity, or current dependence of the inductance, which enables low-noise microwave parametric amplification [20]. Different materials studied in the literature include niobium nitride (Nb-N) [21][22], titanium nitride (Ti-N) [23][24], niobium titanium

• niobium and titanium targets [33] in an ATC2200 from AJA International Inc., with a deposition rate of roughly 3 nm/min. (b) Pads and markers. A lift-off process defines the gold contact pads and alignment marks. We spin a 400 nm thick photoresist (maN1407), bake on a hotplate at 100 °C for 60 s and

Spin dynamics in superconductor/ferromagnetic insulator hybrid structures with precessing magnetization

• Yaroslav V. Turkin and
• Nataliya Pugach

Beilstein J. Nanotechnol. 2023, 14, 233–239, doi:10.3762/bjnano.14.22

• to the Fermi distribution function. Results and Discussion For the numerical calculations, we have considered niobium as a superconducting metal with the following parameters: Tc = 9.2 K, Δ(0) ≈ 1.76kB·Tc = 1.4 meV, D = 0.8·10−3 m2·s−1, and εF ≈ 5.32 eV. We approximate the DOS on the Fermi level with

The influence of structure and local structural defects on the magnetic properties of cobalt nanofilms

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Olesya Severyukhina and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2023, 14, 23–33, doi:10.3762/bjnano.14.3

• structure close to the hexagonal close-packed crystal lattice was considered. In the second case, a cobalt nanofilm formed in the previously obtained numerical experiment of multilayer niobium–cobalt nanocomposite deposition was investigated. The sizes of the systems were the same in both cases. For both

• properties of the nanomaterial were investigated in this work using a promising nanocomposite formed by alternating layers of cobalt and niobium. The proposed composite has potentially promising functional properties and can be used in magnetic systems with controlled effective energy exchange in Josephson

• complex multistage process. The general scheme of the problem-oriented analysis of a multilayer composite of niobium and cobalt is presented in Figure 1. At the preparation stage of the conceptual model, the expected requirements to the main properties of the predicted material are formulated, a

Coherent amplification of radiation from two phase-locked Josephson junction arrays

• Mikhail A. Galin,
• Vladimir M. Krasnov,
• Ilya A. Shereshevsky,
• Nadezhda K. Vdovicheva and
• Vladislav V. Kurin

Beilstein J. Nanotechnol. 2022, 13, 1445–1457, doi:10.3762/bjnano.13.119

• straight electrodes with niobium JJs have been directly visualized recently using low-temperature scanning laser microscopy [13]. The scans revealed that the standing waves can provide the global coupling of all junctions in the array, that is, extended parts of the array can interact with each other. This

• a superconductive to a resistive state observed in all IVCs is typical for niobium junctions with medium doping Si interlayer 11% [18]. Resonant steps at similar voltages are observed for both pairs of arrays. As shown earlier [9][13], they are caused by standing wave (cavity mode) resonances in the

• sample-1. Red squares represent the JJs, which are between the top (orange rectangles) and the bottom (partly covered blue rectangles) niobium electrodes. (c) Geometry of the right part of sample-2 with 380 JJs in each linear array. In the measurements with either of the samples, the outer array-a was

Tunable superconducting neurons for networks based on radial basis functions

• Andrey E. Schegolev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Igor I. Soloviev,
• Mikhail Yu. Kupriyanov,
• Maxim V. Tereshonok and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2022, 13, 444–454, doi:10.3762/bjnano.13.37

• [61][62]: where ρS is the resistivity of the superconducting material, μ0 is the vacuum permeability and ℏ is Planck’s constant. For instance, for a homogeneous niobium film, the estimate for the constant λ0 is around 100 nm, while experimentally measured values of the screening length λ at T = 4.2 K

• times during switching between states with parallel and antiparallel magnetization orientations. We also made some estimates for the quantitative value of the kinetic inductance of the structure shown in Figure 7 based on niobium technology. The inductance of the strip with width W = 100 nm, length X

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

Interface interaction of transition metal phthalocyanines with strontium titanate (100)

• Reimer Karstens,
• Thomas Chassé and
• Heiko Peisert

Beilstein J. Nanotechnol. 2021, 12, 485–496, doi:10.3762/bjnano.12.39

• Tübingen, Germany 10.3762/bjnano.12.39 Abstract We study interface properties of CoPcFx and FePcFx (x = 0 or 16) on niobium-doped SrTiO3(100) surfaces using mainly X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. For all studied molecules, a rather complex, bidirectional charge

• increased by introducing oxygen vacancies into the crystal structure or by doping (e.g., n-type doping with niobium, Nb5+). Generally, two different terminations of STO(100) are known, that is, the surface can be either TiO2- or SrO-terminated. The TiO2 termination can be achieved by (ex situ) acid

• TMPcs allow for the study of both the influence of the ionization potential and the central metal atom on the properties of interfaces with differently prepared STO surfaces. Experimental Niobium-doped strontium titanate (100) (Nb:STO) single crystals were purchased from MaTeck GmbH (Jülich, Germany; 10

Self-standing heterostructured NiC_x-NiFe-NC/biochar as a highly efficient cathode for lithium–oxygen batteries

• Shengyu Jing,
• Xu Gong,
• Shan Ji,
• Linhui Jia,
• Bruno G. Pollet,
• Sheng Yan and
• Huagen Liang

Beilstein J. Nanotechnol. 2020, 11, 1809–1821, doi:10.3762/bjnano.11.163

• lithium–oxygen batteries. It significantly reduced the overpotential and exhibited high efficiency towards ORR and OER [27]. Mu et al. reported that 2D niobium carbide (NbC) nanosheets exhibited enhanced catalytic activity and durability towards ORR [28]. Although progress has been made in the development

Molecular dynamics modeling of the influence forming process parameters on the structure and morphology of a superconducting spin valve

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Vladimir Boian,
• Roman Morari and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1776–1788, doi:10.3762/bjnano.11.160

• This work is a study of the formation processes and the effect of related process parameters of multilayer nanosystems and devices for spintronics. The model system is a superconducting spin valve, which is a multilayer structure consisting of ferromagnetic cobalt nanolayers separated by niobium

• structural quality of superconducting niobium layers, for example, with a thickness comparable to the coherence length of approximately <10 nm, is worse than that of thicker films, and the destructive effect of the interface roughness also suppresses the manifestation of interference effects in ultrathin

• is a high risk of mutual diffusion and the formation of a thick “dead” layer, which also suppresses the transparency of the S/F interface [20]. In the case of materials wetting and limited mutual solubility (as in niobium–nickel and niobium–cobalt, with solubility of about 5% at room temperature

Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

• Sergey Bakurskiy,
• Mikhail Kupriyanov,
• Nikolay V. Klenov,
• Igor Soloviev,
• Andrey Schegolev,
• Roman Morari,
• Yury Khaydukov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1336–1345, doi:10.3762/bjnano.11.118

• prepared by using the magnetron sputtering system Leybold Heraeus Z-400 during a single deposition cycle without depressurization of the chamber. Only three targets were used for the structure preparation: niobium (99.95% purity) was used as a superconducting Cooper pair generator and interlayer separator

• resistance is noticed above critical temperature and after that there is a quick decrease to zero in the critical temperature region at 7.3 K. Niobium enters a superconducting state within the entire volume of sample. The uppercase letters indicate a voltmeter contact connection in the principal scheme of

Proximity effect in [Nb(1.5 nm)/Fe(x)]₁₀/Nb(50 nm) superconductor/ferromagnet heterostructures

• Yury Khaydukov,
• Sabine Pütter,
• Laura Guasco,
• Roman Morari,
• Gideok Kim,
• Thomas Keller,
• Anatolie Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2020, 11, 1254–1263, doi:10.3762/bjnano.11.109

• the thickness of the Fe layer to x = 4 nm the intermediate phase disappears. We attribute the intermediate state to proximity induced non-homogeneous superconductivity in the structure. Keywords: ferromagnet; iron (Fe); mixed state; neutron reflectometry; niobium (Nb); proximity effects

• following work of the same group [39] the modification of IEC by hydrogen uptake was reported. An advantage of niobium as N spacer is that it is the superconducting material with the highest bulk TC = 9.3 K among all elemental superconductors. However, the thickest Nb spacer layer where AP alignment is

• thickness of the entire structure, that is, the current flows not only along the SL but also through the thick niobium layer or at least through its upper part. First of all, we note that a stand-alone Fe/Nb SL structure itself hardly can be a superconductor due to the absence of a clean and oriented Nb

Epitaxial growth and superconducting properties of thin-film PdFe/VN and VN/PdFe bilayers on MgO(001) substrates

• Wael M. Mohammed,
• Igor V. Yanilkin,
• Amir I. Gumarov,
• Airat G. Kiiamov,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2020, 11, 807–813, doi:10.3762/bjnano.11.65

• small-scale computer based on superconducting logic and cryogenic memory that is energy-efficient, scalable and able to solve interesting problems”, opening prospects of reaching 100 PFLOPS/s with about 200 kW of electric power consumption including the cryogenic cooling. Niobium-based Josephson

• of niobium as a superconductor with a Pd1−xFex alloy as a soft and weak ferromagnet was considered as material of choice for superconducting magnetic random access memories (MRAM) [8][29][30]. However, no further developments towards a prototype using a Pd1−xFex alloy have been demonstrated. There

• are indications of non-homogeneous, nanoclustered magnetism in Pd0.99Fe0.01 films grown on niobium [31], which may cause a shortening of the spin-memory length [32] and a reduction of the Josephson critical current. In general, the metallic Nb lattice (body-centered cubic with aNb = 329.4 pm) poorly

Periodic Co/Nb pseudo spin valve for cryogenic memory

• Nikolay Klenov,
• Yury Khaydukov,
• Sergey Bakurskiy,
• Roman Morari,
• Igor Soloviev,
• Vladimir Boian,
• Thomas Keller,
• Mikhail Kupriyanov,
• Anatoli Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2019, 10, 833–839, doi:10.3762/bjnano.10.83

• )/Co(2.5 nm)/Nb(8 nm)]6/Co(1.5 nm)/Nb(25 nm) structure. We took niobium as a superconducting material since it has the highest TC = 9.25 K among all elemental superconductors and forms stable structures with cobalt [19][26][27][28][29][30]. The thickness of the Nb-spacer was chosen to be close to ξS

• the substrate. For high repeatability of the thicknesses of thin Nb films, an electrical motor was used to move the target above the substrate at an equal speed so that the thickness of the niobium layer remains the same for each of the periods of the structure. The growth film rate is 1 nm/s and 0.1

Ternary nanocomposites of reduced graphene oxide, polyaniline and hexaniobate: hierarchical architecture and high polaron formation

• Claudio H. B. Silva,
• Maria Iliut,
• Christopher Muryn,
• Christian Berger,
• Zachary Coldrick,
• Vera R. L. Constantino,
• Marcia L. A. Temperini and
• Aravind Vijayaraghavan

Beilstein J. Nanotechnol. 2018, 9, 2936–2946, doi:10.3762/bjnano.9.272

• size) were used as received. Aniline (Merck) was distilled under reduced pressure prior to use. Niobium pentoxide (Companhia Brasileira de Metalurgia e Mineração, CBMM) was used as received. All other chemicals (Sigma-Aldrich) were also used as received. Preparation of graphene oxide and reduced

Hydrothermal synthesis of ZnO quantum dot/KNb₃O₈ nanosheet photocatalysts for reducing carbon dioxide to methanol

• Xiao Shao,
• Weiyue Xin and
• Xiaohong Yin

Beilstein J. Nanotechnol. 2017, 8, 2264–2270, doi:10.3762/bjnano.8.226

• by reducing CO2 in isopropanol to methanol under UV-light irradiation. Experimental Catalyst synthesis Niobium oxide (Nb2O5, 99.99 wt %) was purchased from Aladdin Industrial Corporation. Potassium hydroxide (KOH, 96 wt %), isopropanol (C3H8O, 99.9 wt %), hydrochloric acid (HCl, 36.5 wt %), zinc

Metal oxide nanostructures: preparation, characterization and functional applications as chemical sensors

• Dario Zappa,
• Angela Bertuna,
• Elisabetta Comini,
• Navpreet Kaur,
• Nicola Poli,
• Veronica Sberveglieri and
• Giorgio Sberveglieri

Beilstein J. Nanotechnol. 2017, 8, 1205–1217, doi:10.3762/bjnano.8.122

• preparation of niobium oxide nanostructures using a hydrothermal technique, during the first experiments we had adhesion problems of the metal layer to the substrates. We changed the thickness of the film, working temperature, KOH molarity and time in order to find out the best conditions to synthetize

• niobium oxide nanostructures directly onto the substrate. Once we achieved reproducible results, nanostructures were investigated in terms of morphology, structural features and functional properties. By using scanning electron microscopy (SEM, LEO 1525) it was possible to verify the presence of the

• nanostructures on alumina substrates and show their morphology. During the hydrothermal treatment Nb2O5 nanoflowers were formed (Figure 7). Raman spectroscopy was performed in order to scrutinize the structural properties of the material. The analysis showed the presence of niobium oxide with residual potassium

Anodization-based process for the fabrication of all niobium nitride Josephson junction structures

• Massimiliano Lucci,
• Ivano Ottaviani,
• Matteo Cirillo,
• Fabio De Matteis,
• Roberto Francini,
• Vittorio Merlo and
• Ivan Davoli

Beilstein J. Nanotechnol. 2017, 8, 539–546, doi:10.3762/bjnano.8.58

• Industriale, Università di Roma “Tor Vergata”, Via del Politecnico, 00133 Roma, Italy 10.3762/bjnano.8.58 Abstract We studied the growth and oxidation of niobium nitride (NbN) films that we used to fabricate superconductive tunnel junctions. The thin films were deposited by dc reactive magnetron sputtering

• investigate its mechanical and adhesion properties. The transport properties of NbN/AlN/NbN Josephson junctions obtained as a result of the above described fabrication process were measured in liquid helium at 4.2 K. Keywords: Josephson effect; superconductors; thin films; tunneling; Introduction Niobium

• (Nb) is the most commonly used material in superconducting electronics [1][2][3], but several groups have been investigating the properties of metals and alloys that could represent an alternative to it. Niobium nitride (NbN), in particular, is a promising material in this respect given its relatively

Thickness dependence of the triplet spin-valve effect in superconductor–ferromagnet–ferromagnet heterostructures

• Daniel Lenk,
• Vladimir I. Zdravkov,
• Jan-Michael Kehrle,
• Günter Obermeier,
• Aladin Ullrich,
• Roman Morari,
• Hans-Albrecht Krug von Nidda,
• Claus Müller,
• Mikhail Yu. Kupriyanov,
• Anatolie S. Sidorenko,
• Siegfried Horn,
• Rafael G. Deminov,
• Lenar R. Tagirov and
• Reinhard Tidecks

Beilstein J. Nanotechnol. 2016, 7, 957–969, doi:10.3762/bjnano.7.88

• sample series investigated in this work was prepared by magnetron sputtering at room temperature on a commercial silicon substrate with a {111} surface. While for the sputtering of the niobium layers, the target was moved over the substrate to obtain a smooth layer of nearly constant thickness, the

Tm-doped TiO₂ and Tm₂Ti₂O₇ pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

• Desiré M. De los Santos,
• Javier Navas,
• Teresa Aguilar,
• Antonio Sánchez-Coronilla,
• Concha Fernández-Lorenzo,
• Rodrigo Alcántara,
• Jose Carlos Piñero,
• Ginesa Blanco and
• Joaquín Martín-Calleja

Beilstein J. Nanotechnol. 2015, 6, 605–616, doi:10.3762/bjnano.6.62

• [5]. TiO2 doping with metallic elements has also been reported, using for example niobium [6], silver [7] or copper [8] as dopants. Many pyrochlore-type compounds (A2B2O7) have been studied to evaluate their semiconductor properties for photocatalytic applications. For example, it is possible to find

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

• vectors of 5:3 resulting in a (SnS)1.20NbS2 stoichiometry. The authors concluded a charge transfer of 0.4 electrons per niobium atom from their calculations. Furthermore, they showed that the Sn 5s orbitals mix strongly with the S 3p orbitals from NbS2. Moreover, vibrational spectroscopy has been used to

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

• photosensitization of nanoporous titanium dioxide, zinc oxide, tin dioxide, niobium oxide, and tantalum oxide by quantum-sized cadmium sulfide, lead sulfide, silver sulfide, antimony sulfide, and bismuth sulfide. They found that the photocurrent quantum yields of these photosensitized transition metal oxides can be

Plasma-assisted synthesis and high-resolution characterization of anisotropic elemental and bimetallic core–shell magnetic nanoparticles

• M. Hennes,
• A. Lotnyk and
• S. G. Mayr

Beilstein J. Nanotechnol. 2014, 5, 466–475, doi:10.3762/bjnano.5.54

• comparability. While some authors found increasing nanoparticle sizes with increasing electrical current of the magnetron gun [13], the results gained with our setup show the opposite trend. Similar findings have been reported recently for the synthesis of niobium NPs [19], in which the temperature profile

Synthesis of LiNbO₃ nanoparticles in a mesoporous matrix

• Anett Grigas and
• Stefan Kaskel

Beilstein J. Nanotechnol. 2011, 2, 28–33, doi:10.3762/bjnano.2.3

• analyses to determine the content of lithium, and niobium were carried out with an ICP-OES Vista (Varian). The samples were digested in hydrofluoric acid with microwave heating at 180 °C for 20 min. The oxygen content was determined with a TCH-600 (Leco) using the carrier gas hot extraction technique. TEM