Author: MAURICIO TERRONES MALDONADO

Nonlinear optical absorption and reflection of single wall carbon nanotube thin films by ZZ-scan technique

MAURICIO TERRONES MALDONADO (2008)

"Both the nonlinear optical transmission and reflection characteristics of HiPco-based single wall carbon nanotube (SWNT) thin films are studied by using the ZZ-scan method with femtosecond laser pulses at a wavelength of 1.46μm1.46μm. The nonlinear absorption coefficient and nonlinear refractive index are obtained as (5.4±2.0)×10−7cm/W(5.4±2.0)×10−7cm∕W and (1.1±0.5)×10−11cm2/W(1.1±0.5)×10−11cm2∕W, respectively, which are considerably greater than those of other optical materials. This large optical nonlinearity is ascribed to (a) homogeneously deposited thin nanotube film on optically transparent barium fluoride, (b) just-resonant excitation condition, and (c) intrinsic saturable absorption feature of SWNTs."

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Curved nanostructured materials

Humberto Terrones Maldonado MAURICIO TERRONES MALDONADO (2003)

"Graphite is a layered material that is very flexible, in which each layer is able to curve in order to form cages, nanotubes, nanocoils, nanocones, etc. In this paper, we demonstrate that various synthetic routes are capable of producing graphite-like nanomaterials with fascinating electronic and mechanical properties. There are other layered systems, which could curl and bend, thus generating novel nanostructures with positive and negative Gaussian curvature. In this context, we will also demonstrate that hexagonal boron nitride, tungsten disulfide (WS2), molybdenum disulfide (MoS2) and rhenium disulfide (ReS2) are also able to create nanocages, nanotubes and nano-arrangements exhibiting novel physico-chemical properties that could revolutionize materials science in the 21st century."

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CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA

Enhanced thermal conductivity of carbon fiber/phenolic resin composites by the introduction of carbon nanotubes

MAURICIO TERRONES MALDONADO Dresselhaus Mildred (2007)

"The authors report a significant enhancement in the thermal conductivity of a conventional carbon fiber/phenolic resin composite system when adding highly crystalline multiwalled carbon nanotubes. They demonstrate that 7wt%7wt% of carbon nanotubes dispersed homogeneously in a phenolic resin acted as an effective thermal bridge between adjacent carbon fibers and resulted in an enhancement of the thermal conductivity (e.g., from 250to393W∕mK250to393W∕mK). These results indicate that highly crystalline carbon nanotubes can be used as a multifunctional filler to enhance simultaneously the mechanical and thermal properties of the carbon fiber/phenolic resin composites."

Article

Polymer composites Fibers CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

An anticorrosive magnesium/carbon nanotube composite

Hiroyuki Muramatsu MAURICIO TERRONES MALDONADO (2008)

"Here, we report a drastically improved anticorrosive characteristic of magnesium alloy composites with the introduction of multiwalled carbon nanotubes. Highly depressed corrosion of nanotube-filled magnesium composite in salt water is due to the formation of stable oxide films along the grain boundaries of magnesium. Our results indicate that carbon nanotube acted as effective multifunctional filler to improve both mechanical and anticorrosive performances of magnesium alloy."

Article

Carbon Fibers CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Novel hetero-layered materials with tunable direct band gaps by sandwiching different metal disulfides and diselenides

HUMBERTO TERRONES MALDONADO FLORENTINO LOPEZ URIAS MAURICIO TERRONES MALDONADO (2013)

"Although bulk hexagonal phases of layered semiconducting transition metal dichalcogenides (STMD) such as MoS2, WS2, WSe2 and MoSe2 exhibit indirect band gaps, a mono-layer of STMD possesses a direct band gap which could be used in the construction of novel optoelectronic devices, catalysts, sensors and valleytronic components. Unfortunately, the direct band gap only occurs for mono-layered STMD. We have found, using first principles calculations, that by alternating individual layers of different STMD (MoS2, WS2, WSe2 and MoSe2) with particular stackings, it is possible to generate direct band gap bi-layers ranging from 0.79 eV to 1.157 eV. Interestingly, in this direct band gap, electrons and holes are physically separated and localized in different layers. We foresee that the alternation of different STMD would result in the fabrication of materials with unprecedented optical and physico-chemical properties that would need further experimental and theoretical investigations."

Article

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS

CdSe quantum dot-decorated double walled carbon nanotubes: the effect of chemical moieties

Hiroyuki Muramatsu MAURICIO TERRONES MALDONADO Dresselhaus Mildred (2008)

"We report that fluorine atoms on the outer tubes of double walled carbon nanotubes (DWNTs) are more effective for nucleating and growing CdSe nanoparticles than oxygen-containing functional groups. The CdSe particles with an average size of 5–7 nm grow through infiltration into an interstitial space created by four to five thin bundled DWNTs. We envisage that DWNTs will replace single and multiwalled carbon nanotubes in a wide range of applications because chemical moieties could be introduced selectively on the outer tubes while the optical and physical properties of the inner tubes remain almost unchanged"

Article

Fluorination CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Controlled growth of one-dimensional clusters of molybdenum atoms using double-walled carbon nanotube templating

Hiroyuki Muramatsu MAURICIO TERRONES MALDONADO Dresselhaus Mildred (2009)

"We report the controlled growth of one-dimensional clusters of molybdenum atoms inside the inner cores of double-walled carbon nanotubes. A combined characterization including high resolution transmission electron microscopy, nitrogen adsorption measurement at 77 K, x-ray photoelectron spectroscopy, Raman spectroscopy, and thermogravimetric analysis reveals that the growth of one-dimensional Mo clusters can be controlled by varying the reaction conditions. The products have specific surface areas of 360–480 m2 g−1360–480 m2 g−1, and their characteristic properties are attributed to the presence of Mo cluster, which affect the electronic structure and can be exploited for the development of nanotube electronic devices."

Article

Adsorption Carbon nanotubes Chemical reactions Electronic structure Metal clusters Molybdenum Nanotechnology Raman spectra Thermal analysis Transmission electron microscopy X-ray photoelectron spectra CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Strong and stable photoluminescence from the semiconducting inner tubes within double walled carbon nanotubes

Hiroyuki Muramatsu MAURICIO TERRONES MALDONADO Dresselhaus Mildred (2009)

"We examined the optical features of single wall carbon nanotubes (SWNTs) and the inner tubes within double walled carbon nanotubes (DWNTs) having the same (n,m) chirality. The brighter and more stable photoluminescence signals as well as the larger absorbance were observed for the semiconducting inner tubes within DWNTs and not for SWNTs. The outer layers of DWNTs maintain the high structural integrity of the inner tubes during both oxidative purification and strong sonication steps and are responsible in increasing the dielectric screening (due to weaker Coulomb interaction); thus leading to a redshift of the E(11)(S) and E(22)(S) excitonic transitions."

Article

Carbon nanotubes Chirality Elemental semiconductors Excitons Photoluminescence; Red shift Semiconductor nanotubes CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Diameter-selective separation of double-walled carbon nanotubes

Hiroyuki Muramatsu MAURICIO TERRONES MALDONADO Dresselhaus Mildred (2008)

"Here, we report a simple and effective way of separating double-walled carbon nanotubes as a function of their diameter using individually dispersed nanotube solutions with the aid of long and random single-stranded DNA. The subtle pHpH change in nanotube solutions gives rise to the preferential coagulation of large-diameter tubes and allows the easy preparation of small-diameter tubes. The stronger van der Waals forces between large-diameter tubes, combined with the decreased solubility of DNA in water at low pHpH, lead to the preferential agglomeration of large-diameter tubes."

Article

Carbon nanotubes Disperse systems DNA pH Phase separation Solubility Texture Van der Waals forces CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Design of graphene electronic devices using nanoribbons of different widths

Gerardo Naumis MAURICIO TERRONES MALDONADO HUMBERTO TERRONES MALDONADO LUIS MANUEL GAGGERO SAGER (2009)

"We present a simple design of a field effect transistor based on graphene nanoribbons, taking advantage of the metallic and semiconductor nature of nanoribbons with different widths. Such device could be constructed by using lithography techniques. The conductance of the proposed device is obtained by using the Kubo formula, assuming a strong damping due to the substrate and imperfections of the lattice. By removing the control electrodes, the design could also be used as an electrical resistance."

Article

Electrical resistivity Field effect transistors Graphene Nanolithography Nanostructured materials CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA