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Search for "layers" in Full Text gives 1173 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Ion beam processing of DNA origami nanostructures
Beilstein J. Nanotechnol. 2024, 15, 207–214, doi:10.3762/bjnano.15.20
- with N2. We also performed several depositions on mica, but the material was found to be unsuitable for the irradiation studies at such high fluences because of significant macroscopic ion-induced damage through cracking and flaking of the upper layers after irradiation. Therefore, in the present study
Graphene removal by water-assisted focused electron-beam-induced etching – unveiling the dose and dwell time impact on the etch profile and topographical changes in SiO2 substrates
Beilstein J. Nanotechnol. 2024, 15, 190–198, doi:10.3762/bjnano.15.18
- extraordinary mechanical and electronic properties. Although many years have passed since its discovery, manipulating single graphene layers is still challenging using standard resist-based lithography techniques. Recently, it has been shown that it is possible to etch graphene directly in water-assisted
- formed, and they start to chemically react with graphene. There are a few possible reaction paths which could occur during this process: A first series of water FEBIE experiments have been performed on single, bi-, and triple layers of graphene in ESEM mode at a background pressure of 130 Pa, with a beam
- studies: A) optical microscopy, B) scanning electron microscopy (SEM), C) AFM, and D) correlative probe and electron microscopy (CPEM). The optical contrast of graphene placed onto SiO2/Si allows us to easily distinguish between its mono-, bi-, triple, and thicker flakes layers. The values (approx. 2.5 nm
Modification of graphene oxide and its effect on properties of natural rubber/graphene oxide nanocomposites
Beilstein J. Nanotechnol. 2024, 15, 168–179, doi:10.3762/bjnano.15.16
- G' value of DPNR/GO could be explained by thin and large surface GO layers. The GO sheet could not withstand large shearing force, causing the rubber particles to slip. The high G' value of DPNR/GO-VTES(a) and DPNR/GO-VTES(b) may be due to hard silica particles, which may contribute to higher energy
CdSe/ZnS quantum dots as a booster in the active layer of distributed ternary organic photovoltaics
Beilstein J. Nanotechnol. 2024, 15, 144–156, doi:10.3762/bjnano.15.14
- relations of refractive indices and extinction coefficient were investigated. The morphologies of the thin films were studied with atomic force microscopy. The chemical boundaries of the ternary layers were determined by Raman spectroscopy. Based on UPS studies, the energy diagram of the potential devices
- was determined. The resistivity of the layers was determined using impedance spectroscopy. Simulations (General-Purpose Photovoltaic Device Model) showed a performance improvement in the cells with quantum dots of 0.36–1.45% compared to those without quantum dots. Keywords: efficiency; luminescence
- -transporting layers [24], active absorbing layers, and other components [25][26]. Inorganic quantum dots are considered substitutes for fullerene acceptors. Their biggest advantages are a tunable band gap, various absorption spectra, and comparatively high mobility of carriers [27][28]. The application of
In situ optical sub-wavelength thickness control of porous anodic aluminum oxide
Beilstein J. Nanotechnol. 2024, 15, 126–133, doi:10.3762/bjnano.15.12
- . Automation software was designed to terminate the anodization process at preset PAAO thickness values. While the concept was illustrated using the widely used method of anodization in a 0.3 M oxalic acid electrolyte with a 40 V potential, it can be readily customized for other protocols. PAAO layers with
- achieve precise optical characterization, one could employ spectroscopic ellipsometry (SE) with more refined division into sub-layers [26] and consider additional material properties, such as the anisotropy of PAAO [27] and the optical dispersion of the refractive index (RI) of Al2O3 [28]. However, for
- attenuate the signal at short and long wavelengths. For very thin PAAO layers (hPAAO < 200 nm), the reflectance spectra did not have significant interferometric features (i.e., Fabry–Pérot-like fringes) in the usable wavelength range of the system. Furthermore, as will be discussed later, at the initial
Influence of conductive carbon and MnCo2O4 on morphological and electrical properties of hydrogels for electrochemical energy conversion
Beilstein J. Nanotechnol. 2024, 15, 57–70, doi:10.3762/bjnano.15.6
- structures were examined in terms of their morphology, electrical properties, and catalytic layers in the OER process. Results and Discussion Characterisation of hydrogel-based polymer composites with dispersed catalytic and conductive particles Scanning electron microscopy (SEM) analysis of hydrogel samples
- presented in this work indicate a promising direction for further work aimed at obtaining electrocatalytic layers participating in the OER process and characterized by high efficiency, while using a simple one-step method for synthesizing a conductive hydrogel containing electrochemically active particles
Nanotechnological approaches in the treatment of schistosomiasis: an overview
Beilstein J. Nanotechnol. 2024, 15, 13–25, doi:10.3762/bjnano.15.2
- . It can have one or multiple layers. Due to that, their size can range from 30 nm to the micrometer range [37]. As drug vehicles, they exhibit unique properties, such as protection of encapsulated compounds from physiological degradation, extended drug half-life, controlled release of the drug
TEM sample preparation of lithographically patterned permalloy nanostructures on silicon nitride membranes
Beilstein J. Nanotechnol. 2024, 15, 1–12, doi:10.3762/bjnano.15.1
- membrane also allows for high-resolution patterning since there is less electron scattering during exposure [26]. The purpose of applying two layers of resist is to create a large undercut by using a bottom layer that is more sensitive than the top layer. This prevents the unwanted deposition of metal that
- techniques, a one-time exposure is possible with the help of high accelerating voltage during electron beam exposure. In this process, rather than doing one resist deposition and exposure after another, the layer selectivity is controlled by the electron beam dose and the sensitivity of the two layers. Only
- in the copolymer (higher sensitivity) the chain scission reaction occurs at low doses; at higher doses, both layers were exposed. The exposure scheme is given in Figure 3. The doses were chosen by considering that the copolymer is 2–3 times more sensitive than PMMA [25]. If the exposure dose is too
A combined gas-phase dissociative ionization, dissociative electron attachment and deposition study on the potential FEBID precursor [Au(CH3)2Cl]2
Beilstein J. Nanotechnol. 2023, 14, 1178–1199, doi:10.3762/bjnano.14.98
- low-energy electron interaction under a variety of different conditions. Those are the gas phase [59][61] in thin layers under non-steady state conditions [57], in comparative FEBID experiments under HV and UHV conditions [60], and with respect to post-deposition purification through electron exposure
- and through reductive halogen removal using atomic hydrogen [58]. In an early study by Spencer et al. [57], 0.7 nm layers of Pt(CO)2Cl2 were exposed to 500 eV electrons and desorbing ligands were monitored by mass spectrometry, while the development of the deposit was monitored using XPS. It was found
Spatial variations of conductivity of self-assembled monolayers of dodecanethiol on Au/mica and Au/Si substrates
Beilstein J. Nanotechnol. 2023, 14, 1169–1177, doi:10.3762/bjnano.14.97
- , Niels Bohrweg 2, 2333 CA Leiden, Netherlands Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Straße 1, 76131, Karlsruhe, Germany 10.3762/bjnano.14.97 Abstract Determining the conductivity of molecular layers is a crucial step in advancing towards applications in molecular
- electronics. A common test bed for fundamental investigations on how to acquire this conductivity are alkanethiol layers on gold substrates. A widely used approach in measuring the conductivity of a molecular layer is conductive atomic force microscopy. Using this method, we investigate the influence of a
- ][3] has always held a central role, as the flexibility and control over the structure of molecules is unmatched. One of the fundamental parts of devices employing a bottom-up approach combined with molecular electronics is comprised of metal electrodes and molecular layers deposited onto them. For
Elasticity, an often-overseen parameter in the development of nanoscale drug delivery systems
Beilstein J. Nanotechnol. 2023, 14, 1149–1156, doi:10.3762/bjnano.14.95
- filled with poly(lactic-co-glycolic acid) (PLGA) cores of different sizes resulting in interfacial water layers with different thicknesses and therefore with tunable elasticity [38]. Semielastic particles whose Young’s moduli were around 50 mPa showed the fastest diffusion in mucus. However, harder
Density functional theory study of Au-fcc/Ge and Au-hcp/Ge interfaces
Beilstein J. Nanotechnol. 2023, 14, 1093–1105, doi:10.3762/bjnano.14.90
- of atomic layers and the epitaxial Au-fcc(001)/Ge(001) heterojunction shown in Figure 2 (two variants of mutual positions of the slabs are presented). This simplest heterostructure can be built by setting the [110] direction of the Au crystal parallel to the [100] direction of the Ge lattice [32
- layers in the supercell. In variant T1 of the considered heterostructure, the Au atoms are at maximum distance from the Ge atoms, while in variant T2 some of the gold atoms are located on the top of Ge sites. Our preliminary calculations indicated that variant T1 is preferred, and we conducted
- tests performed to find the optimal thickness of the Au layer in the Au/Ge heterostructure with five Ge layers. The plot of the interfacial energy reveals a much weaker dependence on the number of Au layers. Values of the work of separation for the Au-fcc(001)/Ge(001) heterojunction include both the
Properties of tin oxide films grown by atomic layer deposition from tin tetraiodide and ozone
Beilstein J. Nanotechnol. 2023, 14, 1085–1092, doi:10.3762/bjnano.14.89
- have been studied from many perspectives. For example, one can mention anodes for Li-ion batteries [1], gas sensors [2], catalytic activities [3], and stable buffer [4] or base [5] layers in solar cells. More applications can be found, when SnO2 is considered as constituent of a nanostructure or a
- nanocomposite layer. ZrO2–SnO2 stacked layers have been shown to perform as mechanically elastic and magnetizable films [6]. SnO2-coated carbon nanotubes have been studied as catalysts [7] and ZnO–SnO2 as functional composite in Li-ion batteries [8]. A recent review article from 2022 lists 27 different
- distances average to less sharp XAS peaks. Because of the somewhat less shallow probe depth of XAS recorded in TEY mode (ca. 10 nm) compared to the high surface sensitivity of the recorded photoemission spectra (a few atomic layers) [41] we suggest that less completely oxidised species appear below the
Isolation of cubic Si3P4 in the form of nanocrystals
Beilstein J. Nanotechnol. 2023, 14, 971–979, doi:10.3762/bjnano.14.80
- phosphorus as a dopant. From the outset, phosphorus diffusion through hydrogenated and oxide layers was surmised to be different. In the case of similar previously performed syntheses of Si NPs with an oxide layer [21], phosphorus diffuses deep into the NP cores and distributes rather homogenously with a
Low temperature atomic layer deposition of cobalt using dicobalt hexacarbonyl-1-heptyne as precursor
Beilstein J. Nanotechnol. 2023, 14, 951–963, doi:10.3762/bjnano.14.78
- . Typically, these systems require ultrathin layers within the nanometre scale [6]. The thickness and conformality criteria of future microelectronics devices require the development of cobalt metal films deposited by ALD. Because of the self-limiting growth process, ALD allows for the sub-nanometre control
- significant influence on the deposition behaviour. Figure 10 shows the thickness distribution of ALD layers deposited at 85 °C after 1500 cycles for different plasma pulse times as violin plot [41]. This plot shows the film thickness distribution on the wafer surface for each plasma pulse time. The results
Upscaling the urea method synthesis of CoAl layered double hydroxides
Beilstein J. Nanotechnol. 2023, 14, 927–938, doi:10.3762/bjnano.14.76
- layers containing MII and MIII octahedral cations connected by μ3-OH bridges that interact electrostatically with interlayer anions. Typically, LDHs can be represented by the chemical formula , where M represents cations (e.g., Mg, Zn, Co, Ni, Cu, Al, Fe, or Cr) and x the metallic ratio (typically, 0.20
Antibody-conjugated nanoparticles for target-specific drug delivery of chemotherapeutics
Beilstein J. Nanotechnol. 2023, 14, 912–926, doi:10.3762/bjnano.14.75
- or elimination of NP targeting capability by shielding or completely covering relevant functional groups. To block the adhesion of corona proteins on NP surfaces, various strategies have been established using surface barrier layers, such as polymer, protein, or biomimetic coatings, with the ultimate
Industrial perspectives for personalized microneedles
Beilstein J. Nanotechnol. 2023, 14, 857–864, doi:10.3762/bjnano.14.70
- artifact from slicing the computer-aided design (CAD) into layers [47][48]. The staircase effect leads to increased surface roughness of the order of micrometers, and high surface roughness on the microneedles will require substantially more pressure to penetrate the skin. These slicing artifacts
Biomimetics on the micro- and nanoscale – The 25th anniversary of the lotus effect
Beilstein J. Nanotechnol. 2023, 14, 850–856, doi:10.3762/bjnano.14.69
- repellency, but also on the capability of some surfaces to keep stable air layers under water – the so-called Salvinia Effect. Such air layers are of great importance for drag reduction (passive air lubrication), antifouling, sensor applications, or oil–water separation. Up to now, based on the
A wearable nanoscale heart sound sensor based on P(VDF-TrFE)/ZnO/GR and its application in cardiac disease detection
Beilstein J. Nanotechnol. 2023, 14, 819–833, doi:10.3762/bjnano.14.67
- “db6 wavelet decomposition” decomposes the heart sound signal into five layers, selects seven optimal bases of the heart sound signal according to the filtering characteristics of the binary wavelet sub-band, and reconstructs feature vectors. As shown in Figure 18, the shaded background annotation
In situ magnesiothermic reduction synthesis of a Ge@C composite for high-performance lithium-ion batterie anodes
Beilstein J. Nanotechnol. 2023, 14, 751–761, doi:10.3762/bjnano.14.62
- compositions such as Li7Ge2, Li9Ge4, and Li22Ge2 [53][54][55]. The remaining shoulder can be ascribed to the decomposition of the electrolyte and the formation of solid–electrolyte interface (SEI) layers [55][56]. In the following cycles, the signal of the SEI layer formation at a potentials of 0.3 V vs Li/Li
Cross-sectional Kelvin probe force microscopy on III–V epitaxial multilayer stacks: challenges and perspectives
Beilstein J. Nanotechnol. 2023, 14, 725–737, doi:10.3762/bjnano.14.59
- consisting of many layers and interfaces. The study and the comprehension of the mechanisms that take place at the interfaces is crucial for efficiency improvement. In this work, we apply frequency-modulated Kelvin probe force microscopy under ambient conditions to investigate the capability of this
- technique for the analysis of an InP/GaInAs(P) multilayer stack. KPFM reveals a strong dependence on the local doping concentration, allowing for the detection of the surface potential of layers with a resolution as low as 20 nm. The analysis of the surface potential allowed for the identification of space
- containing numerous layers and interfaces [1]. The capability to conduct local investigations at the nanoscale level that provide information on the electrical properties of materials and along physical interfaces is becoming crucial for solar photovoltaic device efficiency improvement [2]. Electrical
A graphene quantum dots–glassy carbon electrode-based electrochemical sensor for monitoring malathion
Beilstein J. Nanotechnol. 2023, 14, 701–710, doi:10.3762/bjnano.14.56
- lowers the detection limit [18]. In an effort to combine the properties of carbon dots and graphene, graphene quantum dots (GQDs) with a size smaller than 100 nm and only a few layers of graphene (3 to 10 layers) have been developed as a new class of carbon nanomaterials [19]. Scientists have explored
- distance, respectively, covered by the GQDs. The variation in size of the GQDs can be determined from the x axis, while from the y axis, the thickness of the GQDs can be obtained. The average thickness of the GQDs is about 2.8 nm, which indicates the presence of 8–9 graphene layers, assuming an interlayer
- containing functional groups are still present in GQDs even after hydrothermal treatment. Due to the nanoscale size of GQDs and a small number of graphene layers, the diffraction peak appears broad [35]. Using the FWHM of the diffraction peak, an average crystallite size of 2.69 nm was calculated for the
The microstrain-accompanied structural phase transition from h-MoO3 to α-MoO3 investigated by in situ X-ray diffraction
Beilstein J. Nanotechnol. 2023, 14, 692–700, doi:10.3762/bjnano.14.55
- octahedron layers in the ⟨100⟩α direction. The octahedron layers are bonded by van der Waals interactions in the ⟨010⟩α direction, crystalizing into the α-MoO3 structure. Keywords: microstrain; molybdenum oxide; phase transition; thermal expansion; Introduction Molybdenum exhibits oxidation states ranging
- ], β-MoO3 [15][16], h-MoO3 [17], γ-MoO3 [18], and the high-pressure phase MoO3-II [19]. α-MoO3 and β-MoO3 are the two most commonly reported molybdenum oxides. α-MoO3 is a thermodynamically stable orthorhombic phase. It is a layered crystal with strong covalent bonding within the layers and weak van
- der Waals coupling between layers [20]. β-MoO3 is a metastable phase in which the MoO6 octahedra share corners in three dimensions to construct a monoclinic structure [16]. h-MoO3 is a metastable hexagonal phase. It has the unique structural characteristic that the MoO6 octahedra chains share corners
Humidity-dependent electrical performance of CuO nanowire networks studied by electrochemical impedance spectroscopy
Beilstein J. Nanotechnol. 2023, 14, 683–691, doi:10.3762/bjnano.14.54
- chemisorption and physisorption at the nanowire interface, which suppress electronic transport inside the p-type semiconductor nanowire but enhance ionic transport in the water layers adsorbed on the nanowire surface. Possible physicochemical processes at the nanowire surface are discussed in line with
- formation of additional physisorbed H2O layers through hydrogen bonding (Figure 3e). The conduction process occurs by the Grotthuss mechanism [29][33][34] of H+ hopping through the network of H2O molecules on the surface (H3O+ + H2O ↔ H2O + H3O+). Higher humidity causes increased concentration of H+ and
- the increasing contribution of ionic conductivity in the water layers. At RH above 60%, the constant phase element and the Warburg element appeared in the equivalent circuit, suggesting an increasing part of water physisorption and condensation. All in all, the influence of these factors can explain
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