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Search for "amorphous" in Full Text gives 478 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
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
- on the direct delivery of water molecules into the scanning electron microscope chamber. This process is called focused electron-beam-induced etching (FEBIE) and was already demonstrated for thin amorphous carbon membranes a decade ago [15]. Oxygen or water vapor can be used for etching graphene [16
- as an unwanted co-deposition of amorphous carbon. Those deposition and etching processes may co-exist and can be controlled to a certain level by the electron flux [23]. The influence of surface kinetics phenomena on the etch profiles has not been considered in the previous works describing the proof
- changes upon stationary exposure were investigated in the work of Stevens Kalceff et al. [24], where the authors observed an increase/decrease in volume of crystalline and amorphous SiO2, respectively. However, the explicit mechanism responsible for the process that considers possible reactions paths with
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
- characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, contact angle, thermal gravimetric analysis, and scanning electron microscopy. The XRD results showed the appearance of an amorphous region of silica particles at a diffraction angle of 22°. The formation of silica was
- the XRD spectra for GO-VTES(a) and GO-VTES(b). The peak at 2θ = 11° belongs to the GO sheet, and a new peak that appeared at 2θ = 22° was assigned to the amorphous silica. The broad peak of GO in GO-VTES may be explained to be due to the intercalation of the GO sheet during modification. Silica was
Berberine-loaded polylactic acid nanofiber scaffold as a drug delivery system: The relationship between chemical characteristics, drug-release behavior, and antibacterial efficiency
Beilstein J. Nanotechnol. 2024, 15, 71–82, doi:10.3762/bjnano.15.7
- after stretching the PLA solution during the electrospinning process displays only a broad scattering band, located at around 2θ = 21.3°, indicating an amorphous structure of PLA nanofibers. Due to the stretching and rapid solidification of the PLA solution during traveling from the needle to the
- collector, the rearrangement of the polymer chains into lamellar packing was limited, resulting in domination of the amorphous region in PLA nanofibers [41]. The XRD patterns of BBR drug-loaded PLA nanofiber scaffolds exhibit a distinct peak similar to that of the PLA nanofiber scaffold without the
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 might be different from etching to a free-standing amorphous SiN membrane. The structural integrity of a free-standing crystalline membrane during KOH etching is still to be investigated. An alternative to KOH etching would be FIB milling [38] or RIE [39]. Lift-off fabrication process. SEM images
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
- amorphous matrixes of carbon with embedded metal crystallites and a gold content of 2–3 atom % [19], 10–40 atom % [20], and 8–20 atom % [21], respectively. This is most likely due to the fact that the CVD process is thermally driven, while in FEBID, the precursor fragmentation is primarily electron driven
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
- interlayer distance compared to variant T2. The Ge–Au bond lengths obtained for the T1 structure, 2.50 Å, are in good agreement with the experimental values for amorphous GeAu alloys, 2.66 Å, [33] and thin films of Au covering a Ge(111) surface, 2.5 Å, [34]. In variant T2 the Au–Ge distance between Au atoms
Experimental investigation of usage of POE lubricants with Al2O3, graphene or CNT nanoparticles in a refrigeration compressor
Beilstein J. Nanotechnol. 2023, 14, 1041–1058, doi:10.3762/bjnano.14.86
- (XRD) analyses were performed. Characterization of Al2O3 nanoparticles The morphological features of the Al2O3 nanoparticles were investigated with the help of FE-SEM micrograph (Figure 2a). It is seen that the Al2O3 nanoparticles exhibit amorphous nature. Thus, it can be stated that the particle size
- of the amorphous nature of the material. It is noted that the Al2O3 nanoparticles used in this study have been previously evaluated and similar XRD results were reported in our previous study [21]. Characterization of graphene nanoplatelets The morphological features of the graphene nanoparticles
Isolation of cubic Si3P4 in the form of nanocrystals
Beilstein J. Nanotechnol. 2023, 14, 971–979, doi:10.3762/bjnano.14.80
- 520.8 cm−1. Interestingly, the observed Raman spectrum for SP900 is very similar to that of the product of silicon and phosphorus MBE co-deposition at 3:2 molar ratio [34]. This substance was reported as amorphous; however, it could contain Si3P4 NPs along with other SixPy compounds. Factor group
- appropriate corrections are made [34]. The broad signal at 475 cm−1, likely corresponding to an amorphous admixture, obscures two high-frequency T2 modes (the position of one of them will be addressed in the IR spectra discussion below). Fundamentally, the consistency between the experiment and computations
- , the less noticeable (400), (331), (422) and (511) signals were observed). Amorphous material is present in the sample, which is most noticeable as a ca. 2 nm layer on the surface of the NPs (Figure 7a). Energy-dispersive X-ray (EDX) elemental maps (Figure 7c,d) for Si Kα and P Kα do not show any
Ultralow-energy amorphization of contaminated silicon samples investigated by molecular dynamics
Beilstein J. Nanotechnol. 2023, 14, 834–849, doi:10.3762/bjnano.14.68
- possible, which includes a minimization of the thickness of the amorphous layer. Focused ion beams of such low energy are generally hard to achieve due to the difficulty of focusing. Some current instruments can utilize focused beams of 500 eV to perform chemical analysis of materials [21], and it is
- coefficient µ > 0.94 and indicates a pristine crystalline structure. This region is situated closer to the bottom of the sample. The second is the amorphous region, where µ < 0.89 and no local order is present. It is located near the surface. The third region is a transitive region that we label “partially
- amorphous region”, where 0.89 < µ < 0.94. The damage induced by ion Ar irradiation has not yet completely disturbed the local order. This region is always located between the crystalline and amorphous slabs. In the crystalline region, the sample is intact, and only thermal vibrations occurs. The amorphous
Nanostructured lipid carriers containing benznidazole: physicochemical, biopharmaceutical and cellular in vitro studies
Beilstein J. Nanotechnol. 2023, 14, 804–818, doi:10.3762/bjnano.14.66
- observed by transmission electron microscopy. Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and small-angle X-ray scattering analyses of the nanoparticles indicated that BNZ might be dispersed in the nanoparticle matrix in an amorphous state. The
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
- cycle, the subsequent cycles yield broad and low-intensity peaks caused by the electrochemical milling of the active material, leading to reduced size and amorphous structures [59][60]. For the Ge@C electrodes, the first cathodic peaks in the potential range of 0.5–1.5 V vs Li/Li+, are assigned to the
ZnO-decorated SiC@C hybrids with strong electromagnetic absorption
Beilstein J. Nanotechnol. 2023, 14, 565–573, doi:10.3762/bjnano.14.47
- that crystalline ZnO particles adhere to the surface of amorphous carbon, and the ZnO content increases as a function of a dosage of ZnNO3·6H2O. The as-prepared SiC@C-ZnO hybrids exhibit effective electromagnetic absorption, which is related to a synergy effect of different dielectric loss processes
- gradually gets weaker with increasing added amounts of ZnNO3·6H2O. Also, a small peak at 26.5°, which corresponds to the (002) reflection of amorphous carbon, can be found in the SCZ samples, especially when the dosage of ZnNO3·6H2O is low. A carbon phase on the SiC surface was obtained through the removal
- amorphous state (Figure 2e). The carbon shell may have a positive effect on the nucleation of ZnO particles. This is because oxygen-containing functional groups (such as carboxyl and hydroxy groups) and structural defects are generated on the SiC@C surface during the in situ carbonization [24], which both
Molecular nanoarchitectonics: unification of nanotechnology and molecular/materials science
Beilstein J. Nanotechnol. 2023, 14, 434–453, doi:10.3762/bjnano.14.35
- and Gong discuss the organization of gels [103]. Specifically, they outline a unique anisotropic hydrogel consisting of uniaxially aligned lamellar bilayers in an amorphous gel matrix. This gel organization exhibits a beautiful structural color that is sensitive to mechanical and chemical stimuli. The
A novel approach to pulsed laser deposition of platinum catalyst on carbon particles for use in polymer electrolyte membrane fuel cells
Beilstein J. Nanotechnol. 2023, 14, 190–204, doi:10.3762/bjnano.14.19
- these materials are significant, as evidenced mainly by the differences in the width of the peaks and the ratio of D to G peak heights. The Vulcan material is not well-ordered (close to amorphous), as evidenced by the large width of the D and G peaks. In contrast, the spectrum of the C-11 material has
Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine
Beilstein J. Nanotechnol. 2023, 14, 165–174, doi:10.3762/bjnano.14.17
- as polymer-like nanoparticles of amorphous carbon with embedded partially sp2-hybridized atomic domains [8]. In this structure, electrons are partially delocalized over the domain area, but a strong coupling of the amorphous host matrix is maintained continuously. CQDs are well known as chemically
Upper critical magnetic field in NbRe and NbReN micrometric strips
Beilstein J. Nanotechnol. 2023, 14, 45–51, doi:10.3762/bjnano.14.5
- the electrical resistivity [6]. This feature is related to the polycrystalline or amorphous nature of these materials when deposited in a thin-film form [4][7][8]. In addition to the applicative interest, the study of these materials is relevant from a fundamental point of view. NbxRe1−x (NbRe) for
The influence of structure and local structural defects on the magnetic properties of cobalt nanofilms
Beilstein J. Nanotechnol. 2023, 14, 23–33, doi:10.3762/bjnano.14.3
- crystallization zones are observed in the formed nanofilms. In addition, there are areas of mixed structures, where the amorphous atomic structure most likely prevails. Quantitatively, the structure of nanofilms can be estimated, for example, by calculating the lattice ideality parameter [45]. This parameter is
Electrical and optical enhancement of ITO/Mo bilayer thin films via laser annealing
Beilstein J. Nanotechnol. 2022, 13, 1589–1595, doi:10.3762/bjnano.13.133
- samples show a polycrystalline structure crystallized in a cubic structure (JCPDS:71-2194) [28]. However, the sample treated with 240 mJ shows an amorphous structure because of the high energy that diffuses gas atoms from the chamber into the surface [29]. The obtained peaks correspond to ITO. It can be
Induced electric conductivity in organic polymers
Beilstein J. Nanotechnol. 2022, 13, 1551–1557, doi:10.3762/bjnano.13.128
- , transparency in the visible spectrum, and high mechanical strength [3][4]. PDP has an amorphous structure with a degree of crystallinity not exceeding 15%. It is characterized by unusually high chemical resistance. The conditions for the selective production of PDP with a molecular weight of more than (50–60
In search of cytotoxic selectivity on cancer cells with biogenically synthesized Ag/AgCl nanoparticles
Beilstein J. Nanotechnol. 2022, 13, 1505–1519, doi:10.3762/bjnano.13.124
- letter number 56540 (Inorganic Crystal Structure Database, ICSD). This pattern corresponds to the crystallographic planes (111), (200), (220), (311), and (222) of the NaCl-type face-centered cubic crystal structure. According to the results, the pineapple peel extract (PPeel extract) is amorphous (i.e
Hydroxyapatite–bioglass nanocomposites: Structural, mechanical, and biological aspects
Beilstein J. Nanotechnol. 2022, 13, 1490–1504, doi:10.3762/bjnano.13.123
- high glass solubility will provide an enhanced delivery of these elements, which are important for bone formation [24][27][28][29]. Boron was shown to promote the formation of amorphous calcium phosphate, which is beneficial for normal metabolism and bone tissue repair; besides, the addition of B2O3 to
Enhanced electronic transport properties of Te roll-like nanostructures
Beilstein J. Nanotechnol. 2022, 13, 1284–1291, doi:10.3762/bjnano.13.106
- the anisotropy of the Te crystal structure [20][21]. However, a fast Fourier transform (FFT) analysis of different areas of the HRTEM images (see Figure 3a) shows that the nanostructures are polycrystalline, with well-oriented large grains and rotated small grains at the edges. Small amorphous areas
- diffraction of amorphous/nanocrystalline materials [24] were not observed. The EDS point analysis (Figure 3b) shows that nanostructures consist of Te, in agreement with the results of the SAED analysis and the above presented EDS analysis of the sample (Figure 1d). The transfer characteristics of the t-Te NW
Studies of probe tip materials by atomic force microscopy: a review
Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104
- . This direction has also developed concerning nanomaterials. Carbon nanotubes are compounded with related materials to produce probes, and the analytical performance of this type of probe is better than that of carbon nanotube probes alone. Nakabayashi et al. [44] proposed using amorphous carbon matrix
- (shell) covered nanotubes to produce reinforced carbon–carbon composite nanotools; combining amorphous carbon with the extreme mechanical properties of CNTs can facilitate the production of nanotools with high aspect ratios. Inappropriate properties such as vibration and flexibility can be controlled
Role of titanium and organic precursors in molecular layer deposition of “titanicone” hybrid materials
Beilstein J. Nanotechnol. 2022, 13, 1240–1255, doi:10.3762/bjnano.13.103
- were deposited on a Si surface. All four processes yielded amorphous Ti–organic films. A growth rate of 10–11 Å/cycle was achieved for the TiCl4–AP process, which is higher when compared to the growth rates 4.3 Å/cycle, 1.2 Å/cycle and 1.4 Å/cycle for TiCl4–HQ, TiCl4–PDA and TiCl4–ODA processes
- anatase TiO2 surface and rutile TiO2 surface and will not adsorb on the Al2O3 surface. A previous study reports that TiO2 films grow well using TiCl4 and H2O on amorphous Al2O3 [55]. However, in our case, the Al2O3 surface model we use is crystalline. It is well known that in an amorphous surface the
- molecular mobility is significantly higher than in any corresponding crystalline form and there is a lower coordination number for atoms in the surface which gives rise to enhanced chemical reactivity of the amorphous surface. These results show that the choice of the surface can have a major impact on the
Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications
Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93
- the recombination of trapped excitons causes the redshifted emission. Liu et al. reported the synthesis of highly photoluminescent CDs, which were then further separated into yellow emitting crystalline graphene quantum dots and green emitting amorphous carbon nanodots using a silica gel column. Even
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