Pdf electronic and magnetic properties of iron chains on. Characterization and magnetic properties of helical carbon. Moreover, the magnetic properties of the pristine and ndoped hcnts have been measured. Magnetic properties of asprepared and chemically modified. To our knowledge, the magnetic properties of this type of composites have not been yet investigated.
The magnetic moment in a magnetic flux parallel to the. Recent calculations have shown that the carbon adatom defects on a graphene sheet and on nanotubes both have a magnetic moment 6, 8. The crystal structure of prepared ferrite checked by xray diffraction shows a typical spinel structure. Magnetic property of the feencapsulated carbon nanotubes cnts was examined. We have prepared three samples to study the doping effect of mwcnts on the. The cnts grown on ptfe layer give higher coercivity than those on of fe film. On the basis of the spinpolarized density functional theory calculations, we demonstrate that partially open carbon nanotubes cnts observed in recent experiments have rich electronic and magnetic properties which depend on the degree of the opening. Studies on structural and magnetic properties of pristine and nickelfilled carbon nanotubes synthesized using lani 5 alloy particles as a catalyst. Amorphous carbon nanotubes acnts with diameters in the range of 750 nm were used as absorber materials for electromagnetic waves. In order to avoid the electromagnetic interference, fabricating the microwave absorber is extremely urgent. Structural and electronic properties of rubidiumintercalated 5, 0 zigzag carbon nanotube m. Tuning the magnetic properties of ironfilled carbon nanotubes. Carbon can bond in different ways to construct structures with completely different properties.
Carbon nanotubes cnts have been widely studied for their. Cnts, however, do not contain any magnetic properties, which restricts their potential for biomedical applications as a targeted drug delivery. Introduction the physical properties of onedimensional 1d nanostructures of magnetic materials are presently the subject of intensive research, taking into account the considerable attention. Synthesis, photoluminescence, and magnetic properties of nitrogendoping helical carbon nanotubes the journal of physical chemistry c acs publications. Magnetic properties of multiwalled carbon nanotubeepoxy. Magnetic properties of carbon nanotubes cns are calculated in the effectivemass theory. This value of saturation magnetization of the composite is a factor of 3. Magnetic properties of aligned fefilled carbon nanotubes. Geometric changes of the regular hexagonal reference structures as well as alterations of their energetic, magnetic, and transport characteristics induced by the presence of the defect. Electronic properties of csintercalated single walled. Effect of sulfur on enhancing nitrogendoping and magnetic properties of carbon nanotubes tongxiang cui, 1 ruitao lv, 1 zhenghong huang, 1 feiyu kang, 1 kunlin wang, 2 and dehai wu 2 tongxiang cui. Pdf purification and magnetic properties of carbon nanotubes.
Bouhrara et al properties of csintercalated single wall carbon nanotubes investigated by 3cs nuclear magnetic resonance m. More specifically, carbon nanotubes functionalized with magnetic particles. The magnetic properties of nanotubes were studied by ajiki and ando 8 using the kp perturbation method however, they found that the susceptibility for the. The special nature of carbon combines with the molecular perfection of singlewall cnts to endow them with exceptional material properties, such as very high electrical and thermal conductivity, strength, stiffness, and toughness. The composite of mnco 3 cnts was acquired by a wet chemical process, and then the hybridization was vulcanized and transformed into mns 2 cnts. Magnetic multiwalled carbon nanotubes with controlled release of epirubicin. Pdf magnetic properties of fe catalysts included in. Different methods yield carbon nanotubes with different morphologies and different quantity of residual catalyst material. High frequency properties of carbon nanotubes and their. Properties of nanocarbon are considered from the standpoint of the interrelation between structural imperfection and magnetic ordering. After the deposition of the catalyst, the growth of nanotubes takes place in two stages.
Chemical vapor deposition using ferrocene as precursor was used for the cnt growth. Mechanical, dielectric, and magnetic properties of the. In the field of catalysis, cnts have been exploited as magnetic catalyst support owing to their large surface area and peculiar electronic properties. Magnetic properties of carbon nanotubes filled with. Elaboration and magnetic properties of cobaltpalladium. Singlewalled carbon nanotubes 205 dices determine whether a swnt will be a metal or a semiconductor. Electronic and magnetic properties of partially open.
Magnetic properties of vacancies in graphene and single. Multiwalled carbon nanotubes along with carbonencapsulated cobalt nanoparticles were generated via a catalytic carbon monoxide disproportionation reaction. Magnetic properties of carbon structures springerlink. The magnetic properties of nanotubes were studied by ajiki and ando 8 using the kpperturbation method however, they found that the susceptibility for the. Fe1xnix alloy nanoparticles encapsulated inside carbon. Magnetic and electronic properties of multiwall carbon. They were discovered independently by iijima and ichihashi and bethune et al. Alignment of carbon nanotubes under low magnetic fields. The cnts were grown on fe or ptfe bilayer film deposited on substrates. Varying ferromagnetic properties depending on the shape, size and type of catalyst are discussed in detail. Cnt are known to depict non zero magnetic moments and a number of previ ous studies have addressed their magnetism. Particularly, the use of carbon nanotubes with ferromagnetic properties as. Le normand3 1belarusian state university of informatics and radioelectronics, minsk, belarus 2scientific and practical materials research center, institute of. Catalyst particles are usually encapsulated in the nanotubes and influence the magnetic respond of the samples.
The magnetic moment in a magnetic flux parallel to the tube axis oscillates as a function of the flux with period determined by the flux quantum and phase depending on. In this work, a simple and effective method was used to prepare the mns 2 cnts carbon nanotubes hybridization for microwave absorption. In particular, fe 3o 4 pt nanoparticles have been loaded on carbon nanotubes cnts figure 9 by a. In order to overcome this hurdle, a plethora of efforts have. Magnetic properties of fe catalysts included in carbon nanotubes. In this paper, we synthesized magnetic phase change microcapsules mpcms, which were dispersed into multi.
Carbon nanotubes often refer to singlewall carbon nanotubes swcnts with diameters in the range of a nanometer. Pdf in this paper we report on the magnetic properties of single and multiwalled carbon nanotubes synthesized using different chemical vapour. Nanomagnetism 227 227 9 magnetic properties of nanocomposites based on magnetically functionalized carbon nanotubes s. The local magnetic properties of the one dimensional inner space of the nanotubes are investigated using c nuclear magnetic resonance spectroscopy of encapsulated fullerene molecules inside single walled carbon nanotubes. The adsorption properties of cnts did not change even after 10 times of recycling. The magnetic properties of carbon nanotubes entail considerable relevance, since the same carbon element supports a variety of magnetic responses depending on its allotropic forms 12. Pdf magnetic properties of carbon nanotubes with low content. Synthesis, photoluminescence, and magnetic properties of.
The alignment of multiwalled carbon nanotubes mwnts has been accomplished through deposition of uniform layers of magnetite maghemite nanoparticles diameter 6. Carbon nanotubes properties and applications cheap tubes. Isotope engineering and magnetically purified nanotubes have been advantageously used on our study to discriminate between the different diamagnetic and. Proximity effect tuned magnetic properties in composites. Magnetic and dielectric properties of carbon nanotubes. Pdf magnetic properties of carbon nanotubes cn s are calculated in the effectivemass theory. Pdf films of oriented carbon nanotubes containing different concentrations of ferrocene 0. Nmr strategies to study the local magnetic properties of carbon nanotubes.
Finite zigzag singlewalled carbon nanotubes swcnts of some nanometers in length and modified by a topological defect of the stonewales type were investigated by density functional theory dft computation. A partially open armchair cnt is converted from a metal to a semiconductor and then to a spinpolarized semiconductor by increasing the length. We tuned the magnetic properties of ironfilled multiwalled carbon nanotubes email protected by careful manipulation of the synthesis parameters in a two zone furnace. Magnetic properties of nanowires guided by carbon nanotubes miguel a. Magnetic properties of carbon nanotubes journal of the. Encapsulation of singlemolecule magnets in carbon nanotubes. Green and facile approach for enhancing the inherent magnetic. Magnetic properties of carbon nanotubes with and without.
The coating of cnts with magnetic nanoparticles was performed by combining the polymer wrapping and layerbylayer lbl. Nmr strategies to study the local magnetic properties of. Preparation, texture, and magnetic properties of carbon nanotubes. The saturation magnetization of composites of carbon nanotubes and cofe 2 o 4 cfo magnetic nanoparticles synthesized through a novel onestep process in the presence of a surfactant sodium dodecylbenzenesulfonate show significant increase, to 208 emug.
The goal of this work is to evaluate the magnetic behavior of mwcntsepoxy composites. Cnt products with distorted sidewalls can be obtained by sassisted growth. The magnetic properties of the carbon nanotubes samples before and after chemical treatment were measured at room temperature in a vibrating sample magnetometer. Magnetic properties of the main allotropic modifications of carbon diamond, graphite, nanographite, nanotubes, and fullerenes are described. Magnetic multiwalled carbon nanotubes with controlled. The results of systematic magnetic property measurements on. Preparation of magnetic carbon nanotubes magcnts for. The magnetic properties of carbon nanotubes entail considerable relevance, since the same carbon element supports a variety of magnetic responses. Cobalt multiwalled carbon nanotubes mwcnt hybrids with an original set of magnetic and electric properties were formed by casting co nanoparticles 35 nm of high aspect ratios within the. Kamalianelectromagnetic properties of inner double walled carbon nanotubes investigated by nuclear magnetic resonance m. Here singlemolecule magnets are encapsulated in carbon nanotubes without affecting the properties of the guest molecules, which may be useful in the development of.
This is due to arrangement of the easy magnetization axis of feencapsulated cnts. Moreover, many fascinating cnt structures can also be found in samples grown with s addition, such as bamboolike cnts, twisted cnts, arborizationlike cnts, and beadlike cnts. Magnetic properties of nanowires guided by carbon nanotubes. Do stonewales defects alter the magnetic and transport. Dynamic mechanical analysis dma and vibrating sample magnetometry vsm were used to investigate the mechanical and magnetic properties of silicone elastomers and mwcnts composites. Synthesis, characterization, and anisotropic electrical properties. The data clearly show that the methods 7 and 8 provide material completely free of ferromagnetic impurities. The magnetic properties of nifilled nanotubes were analyzed using a superconducting quantum interference device which revealed their ferromagnetic. Characterization and magnetic properties of helical carbon nanotubes and carbon nanobelts synthesized in acetylene decomposition over fe. Electromagnetic wave absorbing properties of amorphous. Carbon nanotubes cnts are tubes made of carbon with diameters typically measured in nanometers. Effect of sulfur on enhancing nitrogendoping and magnetic. Pdf studies on structural and magnetic properties of. Since carbon based nanostructures can presently be produced very efficiently and reliably nanotubes, graphene, bucky balls, and other fullerenes are all made of carbon, finding a way to manipulate nanosized carbon elements to become magnetic would open the door to a completely new class of magnetic devices for magnetic storage, sensors, and data processing.
66 764 1327 1277 1505 1193 1590 685 80 1594 867 1508 1385 502 240 30 1542 834 371 1308 873 273 665 1274 1101 379 1140 1259 279 511 793 1274