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Nanopages
Authors:
Elena Burakova
,
Alexandr Melezhyk
,
Alyona Gerasimova
,
Evgeny Galunin
,
Nariman Memetov
, and
Alexey Tkachev

] Boncel S. , Koziol K. , Walczak K.Z. , Windle A.H. , Shaffer M.S.P. ( 2011 ) Infiltration of highly aligned carbon nanotube arrays with molten polystyrene . Mater Lett 65 2299 – 2303 . [3

Open access
Nanopages
Authors:
Robert Vajtai
,
Sujit K. Biswas
,
Binqing Wei
,
Gouwen Meng
,
Yung Joon Jung
, and
Pulickel M. Ajayan

Single and multiwalled carbon nanotubes have attracted significant interest due to their one-dimensional structure and unique electrical and mechanical properties. Among the wide variety of their potential applications most importantly they offer potential to serve as building blocks for future electronic device architectures [1, 2, 3, 4, 5, 6]. Carbon nanotubes may serve as active or passive electronic elements; and as passive elements they may serve as interconnects both on short and long ranges [7, 8]. The most essential prerequisite for realizing CNT architectures is to be able to grow nanotubes at controlled sites, in predetermined orientations and to form interconnections. Significant progresses in growing aligned carbon nanotube films have been made recently with a combined approach of the floating catalyst method using pre-patterned templates and chemical vapor deposition (CVD) [9, 10, 11, 12]. Recently we summarized our work on growing architectures of carbon nanotubes, which might be integrated into microelectronic circuits [13]. While the predefined growth of the above mentioned large nanotube structures is important and receives a lot of attention characterization of the product also deserves similarly high attention being a key for future applications and giving the real importance and purpose of the growth efforts. In this paper, we report some of our works, which are directed towards electrical tests on CNTs, namely high current carrying capacity; vertically organized multiwalled nanotubes showing the possible usage of highly ordered and well-shaped tubes; and characterization of singlewalled nanotube junctions.

Open access

, and automation by adding a sorbent to the extract to remove matrix contaminants. Recently, DSPE has been successfully used to purify liquid samples and extracts [ 16–19 ]. Here, single-walled carbon nanotubes (SWNTs) were prepared by an arc discharge

Open access
Nanopages
Authors:
J. B.Nagy
,
J. N. Coleman
,
A. Fonseca
,
A. Destrée
,
Z. Mekhalif
,
N. Moreau
,
L. Vast
, and
J. Delhalle

Organic polymers - carbon nanotubes nanocomposites are synthesized either by mechanical mixing of the two components or by covalently linking the nanotubes to the matrix. The various procedures will be overviewed and the determining factors will be identified for the best mechanical properties of the composites. On the other hand, it will be shown that for highest electrical conductivity much smaller amounts of carbon nanotubes are needed if the nanotubes can be aligned. The thermal conductivity of the nanocomposites will also be overviewed. Finally, together with nanoclay particles, nanotubes are inducing remarkable flame retardant properties in the nanocomposites materials.

Open access
Nanopages
Authors:
D. Carta
,
S. Bullita
,
A. Falqui
,
M. Casula
,
A. Corrias
, and
Z. Kónya

A series of Fe/Co based nanocomposites where the matrix is mesoporous ordered cubic Im3m silica (SBA-16 type) characterized by a three dimensional cage-like structure of pores were obtained by two different approaches: impregnation and gelation. X-ray diffraction and transmission electron microscopy analysis show that after metal loading, calcination at 500 °C and reduction in H2 fl ux at 800 °C the nanocomposites retain the well-ordered structure of the matrix with cubic symmetry of pores. All nanocomposites prepared were tested for the production of carbon nanotubes by catalytic chemical vapour deposition. Transmission electron microscopy points out that good quality multi-walled carbon nanotubes are obtained.

Open access
Nanopages
Authors:
I. Sayago
,
M. Fernández
,
J. Fontecha
,
M. Horrillo
,
A. Seral-Ascaso
,
R. Garriga
, and
E. Muñoz

Carbon nanotube (CNT) networks offer fascinating opportunities as active layers for gas sensor devices. We here review our work on the use of CNT fi lms prepared by airbrush spraying as sensitive layers in resistive sensor devices for gas detection. The sensor fi lms were fabricated by airbrushing nanotube dispersions on alumina substrates. Networks of different CNT materials were tested as active sensing element sensors for the detection of pollutant gases (H2, NO2, octane, toluene, NH3). Our results indicate that the CNT structure and chemical functionalization affect both the CNT entanglement within the airbrushed networks and their gas sensing performance. Thus, highly sensitive NO2 and H2 resistive sensors were fabricated out of networks of carboxylic acid functionalized double-walled carbon nanotubes and Pd-functionalized single-walled carbon nanotubes, respectively. Issues related to gas sensing mechanisms of the tested resistive sensors, and device performance dependence upon the sensor operation temperature are also discussed here. All tested resistive sensors provided negligible responses to interfering gases such as NH3, toluene and octane. CNT-based gas sensors made by other fi lm preparation techniques are also reviewed, and their gas sensor performance is compared to those reported here.

Open access
Journal of Flow Chemistry
Authors:
Patrizio Salice
,
Emiliano Rossi
,
Alessandro Pace
,
Prasenjit Maity
,
Tommaso Carofiglio
,
Enzo Menna
, and
Michele Maggini

The covalent chemistry of carbon nanostructures has put forth a wide variety of interesting derivatives that widen their potential as functional materials. However, the synthetic procedures that have been developed to functionalize the nanostructures may require long reaction times and harsh conditions. In this paper, we study the continuous flow processing of single-wall carbon nanotubes with azomethine ylides and diazonium salts and demonstrate that this approach is effective to reduce reaction times and tune the properties of the functionalized carbon materials.

Open access

complex metabolites and complicated pretreatments in biological samples, it is necessary to determine silodosin by an appropriate adsorbent material for the enrichment. The discovery of carbon nanotubes (CNTs) had brought an increasing number of

Open access
Nanopages
Authors:
A. Szabo
,
A. Fonseca
,
L. P. Biro
,
Z. Konya
,
I. Kiricsi
,
A. Volodin
,
C. Van Hasendonck
, and
J. B.Nagy

Some recent results on the synthesis of coiled carbon nanotubes (CNTs) are summarized. Several supported catalysts can lead to the formation of coiled CNTs. Interestingly, certain domains of the coil pitch and coil diameter are favoured, and two “stability islands”are found in the 3D representation of the number of coiled CNTs as a function of both coil pitch and coil diameter. It is emphasized that these nanotubes are formed either by introducing pairs of five-membered ring - seven-membered ring or by forming haeckelite structures. The coiled CNTs could be used in nanocomposite reinforcement as well as special sensors based on their remarkable mechanical and electrical properties.

Open access

, safety, and automation. Recently, this method has been successfully used to clean up liquid samples or the extracts of various samples [ 15 – 21 ]. Carbon nanotubes are characterized by physicochemical properties, such as stronger adsorption capacity and

Open access