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93
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Introduction
Experienced Researcher skilled in Scanning Probe Microscopy of Graphene, Carbon Nanotubes, and Hybrid Nanostructures.
Current institution
Additional affiliations
October 2016 - present
January 2015 - September 2016
September 2012 - December 2014
Hungarian Academy of Sciences, Research Centre for Natural Sciences (TTK)
Position
- Research Associate
Publications
Publications (93)
Graphene-covered silver nanoparticles were prepared directly on highly oriented pyrolytic graphite substrates and characterized by atomic force microscopy. UV–Vis reflectance spectroscopy was used to measure the shift in the local surface plasmon resonance (LSPR) upon exposure to acetone, ethanol, 2-propanol, toluene, and water vapor. The optical r...
Graphene has numerous outstanding physical properties such as excellent electron mobility, extremely high thermal conductivity, high flexibility, remarkable mechanical strength, and high transparency [...]
Here we report a new method combining strain and defect engineering for the periodic modulation of the graphene nanoscale rippling. First, gold nanoparticles of 16 nm in diameter were synthesized by seed-mediated, wet-chemical approach, and thiol-terminated polyethylene glycol (mPEG-SH) molecules were grafted onto their surface. High-density monola...
Silver nanoparticles (Ag NPs) play important roles in the development of plasmonic applications. Combining these nanoparticles with graphene can yield hybrid materials with enhanced light–matter interaction. Here, we report a simple method for the synthesis of graphene–silver nanoparticle hybrids on highly oriented pyrolytic graphite (HOPG) substra...
The direct experimental probing of locally varying lattice parameters and anisotropic lattice deformations in atomic multilayers is extremely challenging. Here, we develop a combined numerical and graphical method for the analysis of irregular moiré superstructures measured by scanning tunneling microscopy (STM) on a small-twist-angle (∼0.6∘) graph...
The direct experimental probing of locally varying lattice parameters and anisotropic lattice deformations in atomic multilayers is extremely challenging. Here, we develop a new combined numerical/graphical method for the analysis of irregular moir\'e superstructures measured by scanning tunneling microscopy (STM) on a small-twist-angle ($\sim$0.6$...
We investigated the vapour sensing properties of different graphene-gold hybrid nanostructures. We observed the shifts in the optical spectra near the local surface plasmon resonance of the gold nanoparticles by changing the concentration and nature of the analytes (ethanol, 2-propanol, and toluene). The smaller, dome-like gold nanoparticles proved...
We investigated the vapour sensing properties of different graphene-gold hybrid nanostructures. We observed the shifts in the optical spectra near the local surface plasmon resonance of the gold nanoparticles by changing the concentration and nature of the analytes (ethanol, 2-propanol, and toluene). The smaller, dome-like gold nanoparticles proved...
Substrate properties might significantly influence the scattering spectra of supported plasmonic nanoparticles due to different damping mechanisms. In this work ITO substrates are modified by the combination of nanosphere lithography and ion-bombardment to create a nanopattern with sharp boundaries between the irradiated and masked regions. The sin...
Graphene on noble-metal nanostructures constitutes an attractive nanocomposite with possible applications in sensors or energy conversion. In this work we study the properties of hybrid graphene/gold nanoparticle structures by Raman spectroscopy and Scanning Probe Methods. The nanoparticles (NPs) were prepared by local annealing of gold thin films...
Graphene on noble-metal nanostructures constitutes an attractive nanocomposite with possible applications in sensors or energy conversion. In this work we study the properties of hybrid graphene/gold nanoparticle structures by Raman spectroscopy and Scanning Probe Methods. The nanoparticles (NPs) were prepared by local annealing of gold thin films...
It is shown that scanning-probe and optical measurements performed on individual gold particles provide direct experimental evidence on the inhomogeneous ligand distribution of tip-selectively cysteamine modified gold nanorods. At higher (10⁻² mM) cysteamine concentration, a well-defined patch is formed at the tips of 115 x 55 nm gold nanorods. Whi...
The development of functional composite nanomaterials based on graphene and metal nanoparticles (NPs) is currently the subject of intense research interest. In this study we report the preparation of novel type of graphene/Sn and graphene/SnOx (1 < x < 2) hybrid nanostructures and their investigation by scanning probe methods. First, we prepare Sn...
The development of functional composite nanomaterials based on graphene and metal nanoparticles (NPs) is currently the subject of intense research interest. In this study we report the preparation of novel type of graphene/Sn and graphene/SnOx (1 < x < 2) hybrid nanostructures and their investigation by scanning probe methods. First, we prepare Sn...
We investigate the local electronic structure of a Sinai-like, quadrilateral graphene quantum billiard with zigzag and armchair edges using scanning tunneling microscopy at room temperature. It is revealed that besides the $(\sqrt{3}\times\sqrt{3})R30${\deg} superstructure, which is caused by the intervalley scattering, its overtones also appear in...
We investigate the local electronic structure of a Sinai-like, quadrilateral graphene quantum billiard with zigzag and armchair edges using scanning tunneling microscopy at room temperature. It is revealed that besides the $(\sqrt{3}\times\sqrt{3})R30${\deg} superstructure, which is caused by the intervalley scattering, its overtones also appear in...
Hybrid materials composed of single walled carbon nanotubes (SWCNTs) as hollow containers and small molecules as fillers possess intriguing physical and chemical properties. Infrared spectroscopy is a useful method in most cases to characterize hybrid systems; however, regardless of the type of small molecule encapsulated in the SWCNT, the IR spect...
Graphene grown by chemical vapour deposition is transferred on top of flat gold nanoislands and characterized by scanning tunnelling microscopy (STM) and atomic force microscopy (AFM). Graphene bubbles are formed with lateral dimensions determined by the size and shape of nanoislands. These graphene bubbles can be squeezed during STM imaging using...
Graphene grown by chemical vapour deposition is transferred on top of flat gold nanoislands and characterized by scanning tunnelling microscopy (STM) and atomic force microscopy (AFM). Graphene bubbles are formed with lateral dimensions determined by the size and shape of nanoislands. These graphene bubbles can be squeezed during STM imaging using...
Using nanoparticles to impart extrinsic rippling in graphene is a relatively new method to induce strain and to tailor the properties of graphene. Here we study the structure and elastic properties of graphene grown by chemical vapour deposition and transferred onto a continuous layer of SiO2 nanoparticles with diameters of around 25 nm, prepared b...
Using nanoparticles to impart extrinsic rippling in graphene is a relatively new method to induce strain and to tailor the properties of graphene. Here we study the structure and elastic properties of graphene grown by chemical vapour deposition and transferred onto a continuous layer of SiO2 nanoparticles with diameters of around 25 nm, prepared b...
Graphene-metal nanoparticle hybrid materials potentially display not only the unique properties of metal nanoparticles and those of graphene, but also additional novel properties due to the interaction between graphene and nanoparticles. This study shows that gold nanoislands can be used to tailor the local electronic properties of graphene. Graphe...
Graphene-metal nanoparticle hybrid materials potentially display not only the unique properties of metal nanoparticles and those of graphene, but also additional novel properties due to the interaction between graphene and nanoparticles. This study shows that gold nanoislands can be used to tailor the local electronic properties of graphene. Graphe...
Heterostructures of 2D materials are expected to become building blocks of next generation nanoelectronic devices. Therefore, the detailed understanding of their interfaces is of particular importance. In order to gain information on the properties of the graphene - MoS2 system, we have investigated MoS2 sheets grown by chemical vapour deposition (...
3C-SiC layers were deposited on Si substrates by using a low temperature buffer layer and the addition of methyl trichloro silane to the gas phase during the high temperature thick film growth. Several samples were grown by varying the deposition temperature and the methyl trichloro silane content in order to study how these parameters affect the l...
Epitaxial iron silicide nanostructures are grown by solid phase epitaxy on Si(0 0 1) and Si(1 1 1), and by reactive deposition epitaxy on Si(0 0 1) substrates. The formation process is monitored by reflection high-energy electron diffraction. The morphology, size, and electrical properties of the nanoparticles are investigated by scanning electron...
Mesoporous silica thin films were patterned at the sub-micron scale utilizing the ion hammering effect in order to combine the advantages of mesoporous character and surface morphology, while preserving the interconnected pore system or creating laterally separated porous volumes surrounded by nonpermeable compact zones. Porous silica coatings were...
Thin (45–50 nm) non-doped and doped (by Sb and Al) polycrystalline Mg stannide films consisting mainly of Mg2Sn semiconductor phase and containing small quantity of Mg2Si phase have been grown by multiple layer deposition at room temperature and single step annealing at 150 °C of the (Sn–Mg) bi-layers on Si(111) n-type wafers with 7.5 Ωcenterdotcm...
Optical and electrical properties of Mg stannide and germanide nanolayers grown by solid phase epitaxy on a Si(111)7×7 substrate have been studied. It was shown that all grown ultrathin (45-90 nm) films are semiconductors with small band gaps: 0.17-0.22 eV for Mg2Sn and Mg2SnxSi1-x, 0.70 eV for Mg2Ge and 0.56 eV for Mg2GexSi1-x. Optical functions,...
Graphene covered metal nanoparticles constitute a novel type of hybrid materials, which provide a unique platform to study plasmonic effects, surface-enhanced Raman scattering (SERS), and metal-graphene interactions at the nanoscale. Such a hybrid material is fabricated by transferring graphene grown by chemical vapor deposition onto closely spaced...
The possibility that non-magnetic materials such as carbon could exhibit a novel type of s-p electron magnetism has attracted much attention over the years, not least because such magnetic order is predicted to be stable at high temperatures. It has been demonstrated that atomic-scale structural defects of graphene can host unpaired spins, but it r...
The electronic properties of graphene can be significantly influenced by mechanical strain. One practical approach to induce strain in graphene is to transfer atomically thin membranes onto pre-patterned substrates with specific corrugations. The possibility of using nanoparticles to impart extrinsic rippling to graphene has not been fully explored...
The properties of graphene nanoribbons are dependent on both the nanoribbon width and the crystallographic orientation of the edges. Scanning tunneling microscope lithography is a method which is able to create graphene nanoribbons with well defined edge orientation, having a width of a few nanometers. However, it has only been demonstrated on the...
Metal-graphene interfaces generated by electrode deposition induce barriers or potential modulations influencing the electronic transport properties of graphene based devices. However, their impact on the local mechanical properties of graphene is much less studied. Here we show that graphene near a metallic interface can exhibit a set of ripples s...
Perturbations of the two dimensional carbon lattice of graphene, such as
grain boundaries, have significant influence on the charge transport and
mechanical properties of this material. Scanning tunneling microscopy
measurements presented here show that localized states near the Dirac point
dominate the local density of states of grain boundaries i...
First experiments on swift ion irradiation of highly oriented pyrolythic graphite led to formation of carbon nanotubes (CNT) at the cascade eruption points. CNT length was in the micron range, which corresponded to an explosive crystallization of the carbon plume with about sound velocity. Multiplicity of CNT walls depended on cascade density: sing...
We studied a possibility of reduction of the surface of graphite fluoride obtained by fluorination of highly oriented pyrolytic graphite (HOPG) by a gaseous mixture of BrF3 and Br2. X-ray diffraction (XRD) revealed a layered structure of the fluorinated product being a second-stage intercalate due to a presence of bromine molecules between the fluo...
Kimutattuk, hogy a nem-hatszöges (n-H) gyűrűket is tartalmazó szén nanoszerkezetek (Y-elágazás, hengerspirálok, stb.) növekedését az n-H gyűrűk beépülésének mikéntje határozza meg, új modellt javasoltunk hengerspirálok szerkezetére. Elsőként készítettünk Si3N4/szén nanocső kompozitokat és megmutattuk, hogy megfelelő szinterelési paraméterek alkalma...
In this work, carbon nanotube samples were produced by aerosol chemical vapour deposition from a solution of ferrocene in benzylamine. The multi-walled nanotubes produced by this method were investigated by TEM, SEM/EDS, scanning tunneling microscopy (STM) and tunneling spectroscopy (STS). The dl/dV curves obtained from the STS measurements showed...
Multi-walled carbon nanotubes irradiated with Ar+ ions of low (5×1011 ions/cm2) and high (1015 ions/cm2) fluences were investigated by STM. Contrary to the case of low fluence irradiation, the defects produced during the high fluence irradiation could not be observed individually, and the surface of nanotubes became rough. Irradiated nanotubes coul...
Amorphous carbon/nickel double layers were irradiated by 30 keV Ga+ ions via focused ion beam. The effect of irradiation on the concentration distribution of all constituents was studied by Auger electron spectroscopy depth profiling and cross sectional transmission electron microscopy, while the morphology change of the sample was determined by at...
Atomic Force Microscopy (AFM) in the tapping (intermittent contact) mode is a commonly
used tool to measure the thickness of graphene and few layer graphene (FLG) flakes on silicon oxide surfaces. It is a convenient tool to quickly determine the thickness of individual FLG films. However, reports from literature show a large variation of the measur...
Atomic Force Microscopy (AFM) in the tapping (intermittent contact) mode is a commonly used tool to measure the thickness of graphene and few layer graphene (FLG) flakes on silicon oxide surfaces. It is a convenient tool to quickly determine the thickness of individual FLG films. However, reports from literature show a large variation of the measur...
Fe/Ag thin films are intensively investigated due to their special magnetic properties. Recently a deposition-order dependent asymmetric interface has been found. When iron is grown on silver, the interface is sharp, while the growth of Ag on Fe results in a long, low-energy tail of the Ag peak in the Rutherford backscattering spectrometry (RBS) sp...
Multiwalled carbon nanotubes have been prepared using catalytic decomposition of solutions of ferrocene in liquid hydrocarbons: n-hexane, benzene and xylenes. The solutions were injected into the reaction furnace using Ar as carrier gas. The experimental investigations were effectuated in a home-made experimental setup using the spray-pyrolysis met...
Commercial few-layer graphite platelets were characterized by atomic force microscopy (AFM). Successive oxidation of the graphite platelets was carried out at 450-550 degrees C in air, and AFM measurements were performed after each oxidation step. The measurements showed that the applied thermal oxidation reduced the dimensions of the platelets. We...
Atomic resolution scanning tunneling microscope (STM) images of native and artificially created defect sites on graphite and carbon nanotubes were compared. The presence of position-dependent coexisting superstructure patterns was identified on all of the investigated samples. The results indicate that superstructure patterns are mainly determined...
Measuring with a spectroscopic ellipsometer we determined the complex dielectric function of completely amorphous silicon carbide prepared by ion implantation. 860 keV Ni+ ions were implanted into single crystalline 4H-SiC to produce thick amorphized layer. Ion beam analysis was applied to assess total amorphization. For this purpose 4He+ ion beam...
We have measured how irradiation by Ar+ and N+ ions modifies electronic conduction in single-wall carbon nanotube (SWNT) networks, finding dramatically different effects
for different thicknesses. For very thin transparent networks, ion irradiation increases localization of charge carriers and
reduces the variable-range hopping conductivity, especi...
Graphite platelets of 1-5 mu m in diameter consisting of a few graphenes were generated from commercially available exfoliated graphite by ultrasonic treatment in benzene (1 mg material in 20 ml solvent) for 3 h. Droplets from the suspension were dispersed on silicon wafer. The graphite platelets were characterized by atomic force microscopy (AFM)....
Si amorphous 41 nm/Cr polycrystalline 46 nm multilayer structure was irradiated by 30 keV Ga + ions with fluences in the range of 25− 820 ions/ nm 2 using a focused ion beam. The effect of irradiation on the concentration distribution was studied by Auger electron spectroscopy depth profiling, cross-sectional transmission electron microscopy, and a...
We study the effect of Ar+ irradiation on the intermediate frequency modes (IFM) in Raman spectra of single-wall carbon nanotubes. We observe new features in the intermediate frequency region from 386 to 635 cm–1 as the defect concentration increases, whereas at the same time there is a decrease of other IFM modes. After annealing in vacuum, the IF...
In this work the STM investigation of nanotube point defects created by ion irradiation (e.g. vacancies) is presented. The defects appeared as hillock-like features on the STM images. These defects were compared with similar features observed on the STM images of as-grown coiled carbon nanotubes. In this case the observed hillock-like features were...
Smooth (0001)AlN surface on a (0001) sapphire substrate was prepared by ammonia Molecular Beam Epitaxy. A continuous (2×2)(1×1) reconstruction phase transition on the (0001)AlN surface under ammonia flux was experimentally investigated by RHEED. The intensity of a fractional (0 1/2) streak was studied as a function of the sample temperature under d...
Kinetics of (0001) Al2O3 surface nitridation and subsequent growth of AlN films on the sapphire substrate by ammonia molecular beam epitaxy (MBE) are investigated. Surface morphology evolution during AlN growth is studied in situ by reflection high energy electron diffraction and ex situ by atomic force microscopy. It is found that the surfaces of...
The atomic resolution scanning tunneling microscopy investigation of a multiwall carbon nanotube bend junction is reported. Atomic resolution images taken at the junction region revealed position-dependent modulation of the electronic density of states, with a period larger than but commensurate to the underlying atomic lattice, attributed to the s...
We study the effect of Ar + -irradiation on electrical transport in an individual single wall carbon nanotube (SWNT), a thin SWNT network and a thick SWNT film. The damage to SWNT structure induced by Ar + -irradiation is characterized by Raman spectroscopy. The electrical conductance both in an individual SWNT and in a thin SWNT network is strongl...
The characteristics of carbon nanotube field effect transistor are investigated after the whole device is irradiated with Ar+ ions. The resistance become much higher due to the electron scattering at vacancies produced by Ar+ irradiation. In addition, the subthreshold slop, S, (dVG/d(log ID)) increases and the Schottky barrier height decreases afte...
Single layers of Fe and Ag, as well as Fe/Ag (iron deposited first) and Ag/Fe bilayers were prepared by molecular beam evaporation onto Si. The samples were investigated with backscattering spectrometry (BS) and atomic force microscopy (AFM). BS spectra of Fe/Ag and Ag/Fe indicate a significant difference at the interface. In the case of Fe/Ag the...
Multi-wall carbon nanotubes (MWCNTs) dispersed on graphite (HOPG) substrate were irradiated with Ar+ ions of 30 keV, using a dose of D=5×1011 ions/cm2. The irradiated nanotubes were investigated by scanning tunneling microscopy (STM) and spectroscopy (STS) under ambient conditions. Atomic resolution STM images revealed individual nanotube defects,...
Despite of the very promising foreseen applications, the use of carbon nanotubes in wider range is still limited by the high production costs. In this paper, our latest results concerning two inexpensive methods of carbon nanotube growth with the promise of industrial upscaling are presented. In case of the DC “arc in water” method, the effect of t...
The injection chemical vapor deposition (CVD) method allows the semi-continuous production of pure multi-wall carbon nanotubes (MWCNTs). In order to find the most efficient catalyst material and carbon source, we investigated the quality and quantity of carbon nanotubes, when different metallocenes (ferrocene, cobaltocene and nickelocene) and hydro...
A systematic study on the controlled growth of large areas of aligned multi-wall carbon nanotube arrays, from ferrocene–benzene precursor, and of nanotube junctions from ferrocene–thiophene precursor, without hydrogen addition, using an injection CVD method easy to scale up for industrial production is reported.A detailed study is presented of how...
Multi‐wall carbon nanotubes
(MWCNTs) dispersed on graphite (HOPG) substrate were irradiated with Ar+ ions of 30 keV, using a low‐dose of D = 5×1011 ions/cm2. The irradiated samples were investigated by scanning tunneling microscopy
(STM) under ambient conditions. Atomic resolution STM images reveal individual nanotube defects, which appear as hil...
Multiwall carbon nanotubes (MWCNTs) dispersed on graphite on highly oriented pyrolytic graphite (HOPG) substrate were irradiated with Ar+ ions of 30 keV. The irradiated samples were investigated by scanning tunneling microscopy (STM) and spectroscopy (STS) in air. The irradiation-induced defects appear as hillocklike protrusions on the nanotube wal...
The present work is devoted to the synthesis of carbon nanotubes by spray pyrolysis method. This procedure is a version of CCVD method (Catalysed Chemical Vapour Deposition). Using a quartz reactor we have studied the influence of the history of the reactor wall surface, the lenght of the reactor and different aliphatic, saturated hydrocarbons as c...
An overview of the available data on carbon nanotube Y junctions is given. The structural models and the transport calculations on the Y junctions are reviewed followed by the various methods, which successfully produced these junctions and the available experimental transport and tunneling data of the grown junctions. In the discussion section, th...
Multi-wall and single wall carbon nanotubes (MWCNTs, SWCNTs) dispersed on graphite (HOPG) and gold substrates were irradiated with two different doses of Ar+ ions. The irradiated samples were investigated by scanning tunneling microscopy (STM) and spectroscopy (STS). The investigation of SWCNTs irradiated with low-dose Ar+ ions revealed isolated de...
Chemical functionalization of carbon nanotubes (CNTs) is essential for many applications. Attachment of functional groups to nanotubes can dramatically increase the solubility of the nanotube material. Sidewall functional groups should react with polymers and improve the mechanical properties of nanocomposites. Tubes interconnected by chemical bond...
In the present paper we report the simultaneous synthesis of single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) by spray-pyrolysis, a type of chemical vapour deposition (CVD) method. The technical characteristics of the home-made experimental set-up are given. The synthesis involves the spray-pyrolysis of ferrocene (...
The scanning tunneling microscopy (STM) observation of arc-grown Y-branched carbon nanotubes and sharp nanotube bends (nano-knees) is reported. A drilled out graphite rod filled with a nickel/yttrium particle mixture was used as the anode in an arc chamber under He atmosphere of 660-mbar pressure. Straight multi-wall nanotubes, Y-branches and nano-...
We performed scanning tunneling microscopy (STM) measurements on few wall carbon nanotubes that exhibited changing diameter. Such change in the diameter may occur if non-hexagonal carbon ring configurations are introduced in the nanotube walls. A few-walled nanotube knee of 4 degrees, with different diameter values on the two sides of the knee was...
Conference code: 61444, Cited By (since 1996): 1, Export Date: 18 January 2013, Source: Scopus, CODEN: PSISD, doi: 10.1117/12.498912, Language of Original Document: English, Correspondence Address: Koós, A.A.; Res. Inst. for Tech. Phys. Mat. Sci., P.O. Box 49, H-1525 Budapest, Hungary; email: koos@mfa.kfki.hu, References: Kónya, Z., Vesselenyi, I.,...
We performed scanning tunneling microscopy (STM) measurements on few wall carbon nanotubes that exhibited changing diameter. Such change in the diameter may occur if non-hexagonal carbon ring configurations are introduced in the nanotube walls. A few-walled nanotube knee of 4 degrees, with different diameter values on the two sides of the knee was...
New polyaniline/nanotube (PANI/NT) composites have been synthesized by ''in situ'' polymerization processes using both multi-wall carbon nanotubes (MWNTs) and single-wall carbon nanotubes (SWNTs) in concentrations ranging from 2 to 50 wt.%. Although no structural changes are observed using MWNTs above a concentration of 20 wt.%, the in situ synthes...
Carbon nanotubes were grown by the evaporation of a fullerene/Ni particle mixture in vacuum, using 532 nm laser pulses of 12–28 μJ from a Nd YAG laser. The evaporated material was deposited on a freshly cleaved graphite (HOPG) surface and the samples were investigated by scanning tunneling microscopy (STM) and AFM. In the present work, we focus on...
Scanning tunneling microscopy (STM) observation of Y-branched carbon nanotubes produced by the arc-discharge method is reported. A drilled out graphite rod filled with a nickel/yttrium particle mixture was used as anode in the arc chamber under He atmosphere of 660-mbar pressure. Straight multi-wall nanotubes and asymmetrical Y-branches were found...
A simple mechano-chemical modification of multiwall carbon nanotubes is described. The use of ball-milling in specific atmosphere allows us to introduce functional groups like thiol, amine, amide, carbonyl, chlorine, etc. onto carbon nanotubes. The resulted functional groups are characterized using infrared spectroscopy and X-ray photoelectron spec...
Straight carbon nanotubes, carbon nanotube ‘knees’, Y-branches of carbon nanotubes, and coiled carbon nanotubes were grown on a graphite substrate by the decomposition of fullerene under moderate heating (450 °C) in the presence of transition metal particles. The grown structures were investigated without any further manipulation by STM. The observ...
Multiwall carbon nanotubes grown by the catalytic decomposition of acetylene over supported Co catalyst were subjected to wet and dry oxidation in order to remove the unwanted products and the catalyst traces. The effects of the purification treatment on the Co content was monitored by physical methods: Rutherford Backscattering Spectrometry (RBS)....
Straight carbon nanotubes, carbon nanotube “knees,” Y-branches of carbon nanotubes and coiled carbon nanotubes were grown on a graphite substrate held at room temperature by the decomposition of fullerene under moderate heating (450 °C) in the presence of 200-nm Ni particles. The grown structures were investigated without any further manipulation b...
For many applications, in particular for those in which transport occurs through carbon nanotubes
(CNT), and for certain characterization techniques too, it is important to know whether traces of the catalyst used to grow the nanotubes are incorporated in the grown tubes. Nuclear analytical techniques (RBS, PIXE) and XRF were applied to investigat...
Investigating the distribution of the scanning tunneling microscope (STM) current through a nanostructured material is a subject of great current interest. In this work, the transmission of an electron wave packet was calculated through a jellium potential model of a carbon nanotube under the tip of a STM. Snapshots of the full three-dimensional (3...
Calculated double differential cross sections are presented for the simultaneous ionization and excitation into the 2p state of the helium atom by fast proton and antiproton impact. We have used the semiclassical impact parameter method and the transition amplitude was calculated in second-order perturbation approximation. We have investigated the...
Különböző szénhidrogének és bennük oldott metallocének porlasztásos pirolízisével előállított szén nanocsövek vizsgálatával megállapítottuk, hogy xilol szénforrás, illetve ferrocén/nikkelocén keverék esetén állíthatóak elő a legjobb minőségű nanocsövek. Nitrogéntartalmú, bambuszos jellegű szén nanocsöveket állítottunk elő különböző összetételű benz...
