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Search for "graphite" in Full Text gives 356 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Microwave-induced electric discharges on metal particles for the synthesis of inorganic nanomaterials under solvent-free conditions
Beilstein J. Nanotechnol. 2020, 11, 1019–1025, doi:10.3762/bjnano.11.86
- copper. Graphitic carbon nitride (g-C3N4) or graphite powder (commercially available) are used as carbon source. g-C3N4 is synthesized and characterized according to [18]. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) confirms the formation of g-C3N4 (Figure S1 in Supporting
- Information File 1). The reactions were carried out in quartz or Teflon beakers. A Teflon beaker also served as a carbon and fluorine source for the experiments. Typically, 100 mg of acid-treated metal powder mixed either with graphite powder or g-C3N4 (50 mg) were placed inside a domestic kitchen microwave
- growth promoter. Typically, a mixture of activated metal (100 mg), sulfur powder (25 mg) and g-C3N4 (50 mg) were added to a Teflon beaker and irradiated with microwaves. It is important to note that in the absence of carbon (graphite/g-C3N4), the arc synthesis yielded a mixture of metal and metal oxide
Atomic layer deposition for efficient oxygen evolution reaction at Pt/Ir catalyst layers
Beilstein J. Nanotechnol. 2020, 11, 952–959, doi:10.3762/bjnano.11.79
- at +40 V for two hours using two graphite plate counter electrodes. Subsequently, they were rinsed with water and ethanol several times. Catalyst coating was performed by atomic layer deposition in a commercial Gemstar 6 reactor from Arradiance. Platinum and iridium were deposited using
Measurement of electrostatic tip–sample interactions by time-domain Kelvin probe force microscopy
Beilstein J. Nanotechnol. 2020, 11, 911–921, doi:10.3762/bjnano.11.76
- exfoliation from bulk graphite [32][33] and deposited on a piece of Si/SiO2. Measurements were carried out using an Asylum Research Cypher AFM connected to a Zurich Instruments HF2 lock-in amplifier. Figure 3 shows the results of the open-loop controller. During the FM-AFM measurement the tip voltage was
Transition from freestanding SnO2 nanowires to laterally aligned nanowires with a simulation-based experimental design
Beilstein J. Nanotechnol. 2020, 11, 843–853, doi:10.3762/bjnano.11.69
- downstream temperature zone. An alumina boat with 0.3 g of a 1:1 w/w% mixture of pulverized SnO2:graphite was placed in the upstream temperature zone. After closing the system, the pressure was pumped down to a vacuum level below 4.6 × 10−5 mbar by means of a turbo molecular pump. This step was performed to
- sites are changed. Furthermore, it should be considered that the gaseous Sn atoms might already partially react with oxygen in the gas phase and that parts of the graphite, which are not used in the reaction with the SnO2 powder, might react with a fraction of the gaseous oxygen. An effect of these
Templating effect of single-layer graphene supported by an insulating substrate on the molecular orientation of lead phthalocyanine
Beilstein J. Nanotechnol. 2020, 11, 814–820, doi:10.3762/bjnano.11.66
- oriented pyrolytic graphite (HOPG) or SiO2, it has been reported that CuPc attains different orientations resulting in substantial differences in donor–acceptor energy level alignment at the interface. Thus, ordering and orientation of these molecules significantly affect charge carrier injection and
- transparency disappears with an increasing number of graphene layers, and the wettability approaches that of graphite. The underlying support substrate is reported to even influence the chemical reactivity of a monolayer of graphene [15]. Most of the orientation studies of MPc on graphene deal with planar MPc
- tunneling [9]. Graphene has similar properties as graphite and is expected to exhibit similar templating effects as observed earlier on graphite due to its sp2-hybridized structure. The vertically stacked monoclinic domains on the graphene surface provide an uninterrupted path for electrical transport and
Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions
Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62
- material Ni(OH)2/graphene oxide has an onset potential of −0.17 V vs Ag/AgCl for ORR, which is 80 to 100 mV more positive than the corresponding onset potentials of unsupported Ni(OH)2 (−0.25 V vs Ag/AgCl) and exfoliated graphite oxide sheets (−0.27 V vs Ag/AgCl) [64]. In another study, Ni-N/C (nickel
Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy
Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60
- pyrolytic graphite (HOPG) or a KBr crystal to negate the effects of varying scales of roughness, which [12] suggests should be a contributing factor. Qualitatively, there is a general mismatch in behavior when comparing the majority of experimental results with the LJ F(z) curves. In particular, the LJ F(z
Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach
Beilstein J. Nanotechnol. 2020, 11, 703–716, doi:10.3762/bjnano.11.58
- properties of a material. S-AFAM is implemented and compared with a conventional technique (resonance tracking-atomic force acoustic microscopy, RT-AFAM). A sample of a graphite film on a glass substrate is analyzed. S-AFAM can be implemented in any AFM system due to its reduced instrumentation requirements
- (Figure 2). To show the capabilities of this technique, a graphite film was sputtered on a glass substrate and characterized by the proposed S-AFAM technique and by conventional RT-AFAM [7]. Mathematical Model Dynamic model In order to extract the resonance frequencies of a free cantilever and a
- reliable method. A conventional AFM mapping of a graphite film on a glass substrate was carried out using a white-noise signal as excitation of the tip–sample interaction. A FFT was computed for each pixel and stored on a hard disk drive. Figure 4c shows that the contact stiffness can be obtained from
Soybean-derived blue photoluminescent carbon dots
Beilstein J. Nanotechnol. 2020, 11, 606–619, doi:10.3762/bjnano.11.48
- synthesized from glassy carbon [16], graphite [26], polymethyl methacrylate (PMMA) [27], and a graphite–cement mixture [6] via LAL in various liquids. In general, there are three major mechanisms contributing to the photoluminescence (PL) of CDs: 1) size-dependent bandgap (quantum confinement), 2) surface
Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique
Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46
- solid electrolyte interface (SEI) on graphite anodes and HOPG [14][15][16], Li metal [17] and on cathode materials [18][19] as well as the changes in particle size during ageing [19][20]. Other AFM modes used for the analysis of ageing are, for example, Kelvin probe force microscopy (KPFM) and
- conductive AFM (CAFM). Luchkin et al. used KPFM to analyse the Li-ion distribution in graphite anodes and found a core–shell structure in aged graphite particles [21]. Wu et al. used KPFM to track the changes in the surface potential of LiCoO2 cathodes during ageing and found a decrease of the surface
- amplitude represents the electromechanical activity [62][63][64]. Similar to the ESM and PFM signal, digital volume correlation (DVC) in combination with in situ X-ray tomography microscopy (XTM) was used by Pietsch et al. [47] for graphite and silicon anodes and by Finegan et al. [48] for a LiMnO2 cathode
Electrochemically derived functionalized graphene for bulk production of hydrogen peroxide
Beilstein J. Nanotechnol. 2020, 11, 432–442, doi:10.3762/bjnano.11.34
- the role of C=O groups in graphene towards sustainable peroxide formation. We demonstrate a versatile single-step electrochemical exfoliation of graphite to graphene with a controllable degree of oxygen functionalities and thickness, leading to the formation of large quantities of functionalized
- also influence the catalytic property of the materials since these EEG samples are derived from bulk graphite using a single-step exfoliation in different electrolytes. The BET isotherms of the EEG samples are shown in Figure 1b. The shape of the nitrogen adsorption and desorption curves displays a
- typical type III behavior, which corresponds to that of a layered material [42][51]. The surface area varies from 46 ± 2 m2/g (G-M1) to 11 ± 2 m2/g (G-M4). The change in the surface area can be attributed to the rate of exfoliation of the graphite rod which in turn depends upon the availability of
Implementation of data-cube pump–probe KPFM on organic solar cells
Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24
- oriented pyrolytic graphite (HOPG) substrate. The sample was electrically connected to the AWG by mounting the HOPG substrate onto a sample holder designed with in situ electrical contacts. The pump signal generated by the AWG was transmitted through a coaxial cable (air side) connected to a twisted pair
An advanced structural characterization of templated meso-macroporous carbon monoliths by small- and wide-angle scattering techniques
Beilstein J. Nanotechnol. 2020, 11, 310–322, doi:10.3762/bjnano.11.23
- porosity on the precursor materials is expected as some materials are better graphitizable than others. For instance, resin-based carbon materials are not graphitizable, while pitch-based carbon materials develop a comparably high structural order upon heat treatment and can be converted into graphite. The
- resin- and pitch-based samples treated at 3000 °C show no general (hkl) reflections as expected for graphite, while the non-templated precursors are converted to graphite at this temperature. This absence of 3D order can be attributed to the confinement and the nanostructure, which hinder the
- ., the structure is between that of turbostratic carbon and that of graphite. Additional reflexes in the range of the (10) maxima shine through, which are due to impurities, but are negligible in the analysis. Since the applied model is only applicable for turbostratic carbon materials, only the 800 °C
Facile biogenic fabrication of hydroxyapatite nanorods using cuttlefish bone and their bactericidal and biocompatibility study
Beilstein J. Nanotechnol. 2020, 11, 285–295, doi:10.3762/bjnano.11.21
- graphite mortar and pestle and placed on the sample holder. The crystallite size and phase formation of the cuttlefish-bone-derived Hap nanorods were identified and confirmed by comparing the data with standard XRD patterns from JCPDS. Fourier transform infrared spectroscopy The presence of functional
Nonequilibrium Kondo effect in a graphene-coupled quantum dot in the presence of a magnetic field
Beilstein J. Nanotechnol. 2020, 11, 225–239, doi:10.3762/bjnano.11.17
- graphene-based nanoelectronic devices. Graphene is a two-dimensional layer of graphite. Such layers were isolated experimentally about a decade ago [1][2] and described theoretically about half a century ago [49]. The carbon atoms in graphene are arranged in a hexagonal (honeycomb) lattice. The hexagonal
- on the bias voltage is in agreement with the theoretical results of Świrkowicz et al., who considered a QD connected to metallic electrodes [31]. The zero-bias peak of the differential conductance was observed experimentally for magnetic impurities induced by vacancies on graphite surface [77]. In
Simple synthesis of nanosheets of rGO and nitrogenated rGO
Beilstein J. Nanotechnol. 2020, 11, 68–75, doi:10.3762/bjnano.11.7
- hybrid systems such as batteries [6], electrodes [7] and photodetectors [8]. In 1958, Hummer and Offeman developed a chemical method to synthesize graphene oxide by acid treatment of graphite [9]. The graphene oxide thus obtained contains oxygen functional groups (–CO–, –COC–) on the surface and edges of
- ], solvothermal [16], hydrothermal synthesis [17], laser reduction of graphite oxide [18][19], and photo thermal deoxygenation of graphene oxide by camera flash have been developed to reduce the oxygen content of GO in order to restore the conjugated network [20]. Recently, a well-known chemical reduction method
Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts
Beilstein J. Nanotechnol. 2020, 11, 1–15, doi:10.3762/bjnano.11.1
- they can result in further advantages such as an improved tolerance towards impurities compared to Pt-based catalysts [1]. A wide variety of N-doped carbon materials is known from the literature, reaching from N-doped graphene and graphite, N-doped carbon nanotubes, carbon cages, carbon cups and carbon
- are chemical vapor deposition (CVD) and arc discharge methods for N-doped graphene, graphite, and carbon nanotubes [9]. Most commonly, the post-synthetic approach is carried out by thermal treatment of carbon in ammonia atmosphere, typically leading to surface N-doping. A variety of N bonding
- thickness of the graphite layers Lc determined by X-ray diffraction measurements. Similar observation was made by Liu et al. for carbon spheres that were synthesized by hydrothermal treatment of a sucrose solution and subsequently graphitized in the presence of nickel-oxide particles. High-resolution TEM
Formation of metal/semiconductor Cu–Si composite nanostructures
Beilstein J. Nanotechnol. 2019, 10, 2497–2504, doi:10.3762/bjnano.10.240
- accelerator (1) irradiates the surface of the source materials (4), which are located in a graphite crucible and consist of two mixed solids. The current has a small value of 5–10 mA. As a result, the source materials are transformed into a liquid state. Then, in the second stage, the beam current rises up to
- of composite nanoparticles. Elements of the installation: 1 – linear electron accelerator ELV-6; 2 – evaporation chamber; 3 – graphite crucible; 4 – evaporated materials; 5 – input pipe for the transport gas; 6 – connecting pipe; 7 – intermediate chamber for cooling the aerosol and partial deposition
Semitransparent Sb2S3 thin film solar cells by ultrasonic spray pyrolysis for use in solar windows
Beilstein J. Nanotechnol. 2019, 10, 2396–2409, doi:10.3762/bjnano.10.230
- PGSTAT302). The contact material for both measurements was deposited from an aqueous graphite ink from Alfa Aesar. S L2,3 soft X-ray emission spectra of Sb2S3 were measured using the SALSA endstation [72], at the open port of Beamline 8.0.1 of the Advanced Light Source (ALS), at Lawrence Berkeley National
Nontoxic pyrite iron sulfide nanocrystals as second electron acceptor in PTB7:PC71BM-based organic photovoltaic cells
Beilstein J. Nanotechnol. 2019, 10, 2238–2250, doi:10.3762/bjnano.10.216
- acquired with a JEOL JSM 7800F. STM [32][33] measurements were carried out under ambient conditions with the Nanosurf Easyscan 2 STM device. For the latter measurements, FeS2 was dissolved in chlorobenzene at a concentration of 0.2 mg/mL and deposited on a highly ordered pyrolytic graphite (HOPG) surface
A novel all-fiber-based LiFePO4/Li4Ti5O12 battery with self-standing nanofiber membrane electrodes
Beilstein J. Nanotechnol. 2019, 10, 2229–2237, doi:10.3762/bjnano.10.215
- small amount of TiO2 was found in the diffraction peaks of Li4Ti5O12 fibers, which may be related to the sintering atmosphere of Li4Ti5O12 fibers. Because the sintering of Li4Ti5O12 fibers was carried out under the pressure of a graphite plate in N2 atmosphere, the sintering atmosphere is a partially
Ultrathin Ni1−xCoxS2 nanoflakes as high energy density electrode materials for asymmetric supercapacitors
Beilstein J. Nanotechnol. 2019, 10, 2207–2216, doi:10.3762/bjnano.10.213
- . Ni1.7Co1.3O4 powder was obtained via heating the powder in air at 350 °C for 2 h. Fabrication of Ni1−xCoxS2 electrode Ni1−xCoxS2 was synthesised in a rapid thermal processing (RTP) tube furnace. A graphite box containing about 20 mg as-prepared Ni1.7Co1.3O4 and sufficient sulfur powder (200 mg) was placed in
Use of data processing for rapid detection of the prostate-specific antigen biomarker using immunomagnetic sandwich-type sensors
Beilstein J. Nanotechnol. 2019, 10, 2171–2181, doi:10.3762/bjnano.10.210
- anti-PSA antibodies were obtained from Abcam, Cambridge, UK. Graphite-based ink was obtained from Henkel Electrodag, USA (reference code 423SS), silver chloride ink was purchased from Gwent electronic materials Ltd., UK (Product code C2130905D3), the cell lines PNT-2 and LNCap were acquired from the
Optimization and performance of nitrogen-doped carbon dots as a color conversion layer for white-LED applications
Beilstein J. Nanotechnol. 2019, 10, 2004–2013, doi:10.3762/bjnano.10.197
- exfoliation of graphite [47]. The obtained CDots showed a broad band emission due to their heterogeneity in particle size and surface-functional groups. The authors explored the potential of CDots as UV-to-visible color converters using a 365 nm UV chip and could generate white light with CIE color
- nanoparticles instead of power spectra, which show diffraction spots generated by only one plane. Figure 2c shows the HRTEM micrograph of a ≈10 nm diameter nanoparticle. This nanoparticle is identified as being composed of a graphite phase based on the observation of the 0.34 nm lattice spacing values
- this lattice spacing as the {1120} lattice plane of graphene [55][56]. It should be noted here that when it comes to CDots, it is common to assign them as graphene rather than graphite, since typically, stacking of a few layers of graphene forms the CDots. The HRTEM micrographs obtained from a ≈9 nm
Tuning the performance of vanadium redox flow batteries by modifying the structural defects of the carbon felt electrode
Beilstein J. Nanotechnol. 2019, 10, 1698–1706, doi:10.3762/bjnano.10.165
- , both electrode surfaces tend to oxidize with the additional formation of oxygen functional groups [9][10]. Excess oxidation of the carbon felt can also introduce nonselective functional groups such as –C–O and –C=O and reduces the sp2 carbon content or the graphite content of the felt. The formation of
- nonselective functional groups can impede the redox reaction. For example, Estevez et al. showed that the presence of –O–C=O groups increases the performance of the VRFB whereas the presence of –C–O and –C=O degrades it [11]. In the long run, reduction in the graphite or sp2 carbon content of the felt reduces
- graphitic nature as functionalization proceeds by breaking of the C6 rings, and in many cases, with the formation of a sp3 hybridized carbon atoms (out of plane with the graphene layer). Moreover, most of these functional groups will be predominantly formed at graphite edge sites which are much more active
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