Gas Adsorption on Suspended Carbon Nanotubes and Graphene

Gas Adsorption on Suspended Carbon Nanotubes and Graphene PDF Author: Boris Dzyubenko
Publisher: Boris Dzyubenko
ISBN:
Category : Science
Languages : en
Pages :

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Book Description
Rare gas adsorption was studied on suspended individual single walled carbon nanotubes and graphene. The devices were fabricated as field effect transistors. Adsorption of N2 and CO, which formed a Root 3 X Root 3 commensurate solid monolayer, produced a dramatic reduction of the two-terminal conductance of graphene by as much as a factor of three. This effect is possibly connected with the opening of a band gap expected to occur in such structures.

Gas Adsorption on Suspended Carbon Nanotubes and Graphene

Gas Adsorption on Suspended Carbon Nanotubes and Graphene PDF Author: Boris Dzyubenko
Publisher: Boris Dzyubenko
ISBN:
Category : Science
Languages : en
Pages :

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Book Description
Rare gas adsorption was studied on suspended individual single walled carbon nanotubes and graphene. The devices were fabricated as field effect transistors. Adsorption of N2 and CO, which formed a Root 3 X Root 3 commensurate solid monolayer, produced a dramatic reduction of the two-terminal conductance of graphene by as much as a factor of three. This effect is possibly connected with the opening of a band gap expected to occur in such structures.

Gas Adsorption on Suspended Carbon Nanotubes and Graphene

Gas Adsorption on Suspended Carbon Nanotubes and Graphene PDF Author: Boris Dzyubenko
Publisher:
ISBN:
Category :
Languages : en
Pages : 167

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Book Description
Rare gas adsorption was studied on suspended individual single walled carbon nanotubes and graphene. The devices were fabricated as field effect transistors. Adsorption on graphene was studied through two-terminal conductance. On nanotube devices adsorption was studied through conductance while the coverage (density) of the adsorbates was determined from the mechanical resonance frequency shifts. The adsorbed atoms modified the conductance of the nanotube field effect transistors, in part through charge transfer from the adsorbates to the nanotube. By tracking the shifts of conductance as a function of gate voltage, G=G(Vg), and comparing these shifts with the periodicity of the Coulomb blockade oscillations we quantified the charge transfer to the nanotubes with high accuracy. For all studied gases (He, Ar, Kr, Xe, N2, CO, and O2) the charge transfer had a similar magnitude and was rather small, on the order of 10^-5 to 10^-3 electrons per adsorbed atom. The nanotube devices displayed two classes of adsorption behavior. On some devices the monolayers exhibited first-order phase transitions analogous to those that occur in adsorbed monolayers on graphite. On other devices phase transitions within the adsorbed monolayers were absent. We present evidence that a highly uniform layer of contaminants deposits on the surface of suspended nanotube devices either upon cooldown in the cryostat or at room temperature from air. These contaminants modify the adsorption behavior preventing the adsorbed monolayers from exhibiting the first order phase transitions expected to occur on a clean surface. A similar type of contamination leading to virtually identical effects occurs on suspended graphene. In the low coverage regions of isotherms on nanotubes we observe Henry's law behavior, demonstrating a high uniformity of the surface and allowing us to accurately determine the single particle binding energy to this surface. The determined binding energies were 776+-10 K for Ar, and 997+-37 K for Kr. In the second part of the dissertation we present the first measurements of adsorption on a pristine graphene surface, exposed through aggressive electric current annealing. On graphene the rare gas adsorbates form monolayers with phases analogous to those on graphite, but with phase transitions occurring at slightly higher pressures due to a reduction of binding energy. The condensations of monolayers with phases not commensurate with the graphene lattice resulted in a slight shift of the charge neutrality point of monolayer graphene corresponding to a change of carrier concentration on the order of 10^9 e/cm^2. Adsorption of N2 and CO, which formed a Root 3 X Root 3 commensurate solid monolayer, produced a dramatic reduction of the two-terminal conductance of graphene by as much as a factor of three. This effect is possibly connected with the opening of a band gap expected to occur in such structures. We observe hysteretic behavior in the adsorbed Root 3 X Root 3 commensurate monolayers on freestanding graphene, which is likely due to the interaction of two adsorbed monolayers on opposite surfaces of the graphene sheet.

Carbon Nanomaterials for Gas Adsorption

Carbon Nanomaterials for Gas Adsorption PDF Author: Maria Letizia Terranova
Publisher: CRC Press
ISBN: 9814316431
Category : Technology & Engineering
Languages : en
Pages : 500

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Book Description
Research in adsorption of gases by carbon nanomaterials has experienced considerable growth in recent years, with increasing interest for practical applications. Many research groups are now producing or using such materials for gas adsorption, storage, purification, and sensing. This book provides a selected overview of some of the most interesting scientific results regarding the outstanding properties of carbon nanomaterials for gas adsorption and of interest both for basic research and technological applications. Topics receiving special attention in this book include storage of H, purification of H, storage of rare gases, adsorption of organic vapors, gas trapping and separation, and metrology of gas adsorption.

Emerging Applications of Carbon Nanotubes and Graphene

Emerging Applications of Carbon Nanotubes and Graphene PDF Author: Bhanu Pratap Singh
Publisher: CRC Press
ISBN: 1000838668
Category : Technology & Engineering
Languages : en
Pages : 369

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Book Description
This book comprehensively reviews recent and emerging applications of carbon nanotubes and graphene materials in a wide range of sectors. Detailed applications include structural materials, ballistic materials, energy storage and conversion, batteries, supercapacitors, smart sensors, environmental protection, nanoelectronics, optoelectronic and photovoltaics, thermoelectric, and conducting wires. It further covers human and structural health monitoring, and thermal management applications. Key selling features: Exclusively takes an application-oriented approach to cover emerging areas in carbon nanotubes and graphene Covers fundamental and applied knowledge related to carbon nanomaterials Includes advanced applications like human and structural health monitoring, smart sensors, ballistic protection and so forth Discusses novel applications such as thermoelectrics along with environmental protection related application Explores aspects of energy storage, generation and conversion including batteries, supercapacitors, and photovoltaics This book is aimed at graduate students and researchers in electrical, nanomaterials, chemistry, and other related areas.

Carbon Nanotubes

Carbon Nanotubes PDF Author: Stefano Bianco
Publisher: BoD – Books on Demand
ISBN: 9533075007
Category : Science
Languages : en
Pages : 372

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Book Description
Since their discovery in 1991, carbon nanotubes have been considered as one of the most promising materials for a wide range of applications, in virtue of their outstanding properties. During the last two decades, both single-walled and multi-walled CNTs probably represented the hottest research topic concerning materials science, equally from a fundamental and from an applicative point of view. There is a prevailing opinion among the research community that CNTs are now ready for application in everyday world. This book provides an (obviously not exhaustive) overview on some of the amazing possible applications of CNT-based materials in the near future.

MEMS and Nanotechnology for Gas Sensors

MEMS and Nanotechnology for Gas Sensors PDF Author: Sunipa Roy
Publisher: CRC Press
ISBN: 1498700136
Category : Technology & Engineering
Languages : en
Pages : 224

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Book Description
How Can We Lower the Power Consumption of Gas Sensors? There is a growing demand for low-power, high-density gas sensor arrays that can overcome problems relative to high power consumption. Low power consumption is a prerequisite for any type of sensor system to operate at optimum efficiency. Focused on fabrication-friendly microelectromechanical systems (MEMS) and other areas of sensor technology, MEMS and Nanotechnology for Gas Sensors explores the distinct advantages of using MEMS in low power consumption, and provides extensive coverage of the MEMS/nanotechnology platform for gas sensor applications. This book outlines the microfabrication technology needed to fabricate a gas sensor on a MEMS platform. It discusses semiconductors, graphene, nanocrystalline ZnO-based microfabricated sensors, and nanostructures for volatile organic compounds. It also includes performance parameters for the state of the art of sensors, and the applications of MEMS and nanotechnology in different areas relevant to the sensor domain. In addition, the book includes: An introduction to MEMS for MEMS materials, and a historical background of MEMS A concept for cleanroom technology The substrate materials used for MEMS Two types of deposition techniques, including chemical vapour deposition (CVD) The properties and types of photoresists, and the photolithographic processes Different micromachining techniques for the gas sensor platform, and bulk and surface micromachining The design issues of a microheater for MEMS-based sensors The synthesis technique of a nanocrystalline metal oxide layer A detailed review about graphene; its different deposition techniques; and its important electronic, electrical, and mechanical properties with its application as a gas sensor Low-cost, low-temperature synthesis techniques An explanation of volatile organic compound (VOC) detection and how relative humidity affects the sensing parameters MEMS and Nanotechnology for Gas Sensors provides a broad overview of current, emerging, and possible future MEMS applications. MEMS technology can be applied in the automotive, consumer, industrial, and biotechnology domains.

Carbon Nanomaterials Sourcebook

Carbon Nanomaterials Sourcebook PDF Author: Klaus D. Sattler
Publisher: CRC Press
ISBN: 1482252694
Category : Science
Languages : en
Pages : 614

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Book Description
The Carbon Nanomaterials Sourcebook contains extensive, interdisciplinary coverage of carbon nanomaterials, encompassing the full scope of the field—from physics, chemistry, and materials science to molecular biology, engineering, and medicine—in two comprehensive volumes. Written in a tutorial style, this first volume of the sourcebook: Focuses on graphene, fullerenes, nanotubes, and nanodiamonds Describes the fundamental properties, growth mechanisms, and processing of each nanomaterial discussed Explores functionalization for electronic, energy, biomedical, and environmental applications Showcases materials with exceptional properties, synthesis methods, large-scale production techniques, and application prospects Provides the tools necessary for understanding current and future technology developments, including important equations, tables, and graphs Each chapter is dedicated to a different type of carbon nanomaterial and addresses three main areas: formation, properties, and applications. This setup allows for quick and easy search, making the Carbon Nanomaterials Sourcebook: Graphene, Fullerenes, Nanotubes, and Nanodiamonds, Volume I a must-have reference for scientists and engineers.

Carbon Nanotubes: Quantum Cylinders of Graphene

Carbon Nanotubes: Quantum Cylinders of Graphene PDF Author:
Publisher: Elsevier
ISBN: 0080569919
Category : Technology & Engineering
Languages : en
Pages : 230

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Book Description
This volume is devoted to mostly to nanotubes, unique synthetic nanoscale quantum systems whose physical properties are often singular (i.e. record-setting). Nanotubes can be formed from a myriad of atomic or molecular species, the only requirement apparently being that the host material or “wall fabric be configurable as a layered or sheet-like structure. Nanotubes with sp2-bonded atoms such as carbon, or boron together with nitrogen, are the champions of extreme mechanical strength, electrical response (either highly conducting or highly insulating), and thermal conductance. Carbon nanotubes can be easily produced by a variety of synthesis techniques, and for this reason they are the most studied nanotubes, both experimentally and theoretically. Boron nitride nanotubes are much more difficult to produce and only limited experimental characterization data exist. Indeed, for boron nitride nanotubes, theory is well ahead of experiment. For these reasons this volume deals largely with carbon nanotubes. Conceptually, the "building block" for a carbon nanotube is a single sheet of graphite, called graphene. Recently, it has become possible to experimentally isolate such single sheets (either on a substrate or suspended). This capability has in turn fueled many new theoretical and experimental studies of graphene itself. It is therefore fitting that this volume contains also a chapter devoted to graphene. - Comprehension- Overview- Highlights in the field

Carbon Nanotubes: From Basic Research to Nanotechnology

Carbon Nanotubes: From Basic Research to Nanotechnology PDF Author: Valentin N. Popov
Publisher: Springer Science & Business Media
ISBN: 1402045743
Category : Technology & Engineering
Languages : en
Pages : 270

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Book Description
It is about 15 years that the carbon nanotubes have been discovered by Sumio Iijima in a transmission electron microscope. Since that time, these long hollow cylindrical carbon molecules have revealed being remarkable nanostructures for several aspects. They are composed of just one element, Carbon, and are easily produced by several techniques. A nanotube can bend easily but still is very robust. The nanotubes can be manipulated and contacted to external electrodes. Their diameter is in the nanometer range, whereas their length may exceed several micrometers, if not several millimeters. In diameter, the nanotubes behave like molecules with quantized energy levels, while in length, they behave like a crystal with a continuous distribution of momenta. Depending on its exact atomic structure, a single-wall nanotube –that is to say a nanotube composed of just one rolled-up graphene sheet– may be either a metal or a semiconductor. The nanotubes can carry a large electric current, they are also good thermal conductors. It is not surprising, then, that many applications have been proposed for the nanotubes. At the time of writing, one of their most promising applications is their ability to emit electrons when subjected to an external electric field. Carbon nanotubes can do so in normal vacuum conditions with a reasonable voltage threshold, which make them suitable for cold-cathode devices.

Carbon Nanotubes and Graphene

Carbon Nanotubes and Graphene PDF Author: Kazuyoshi Tanaka
Publisher: Newnes
ISBN: 0080982689
Category : Science
Languages : en
Pages : 458

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Book Description
Carbon Nanotubes and Graphene is a timely second edition of the original Science and Technology of Carbon Nanotubes. Updated to include expanded coverage of the preparation, purification, structural characterization, and common application areas of single- and multi-walled CNT structures, this work compares, contrasts, and, where appropriate, unitizes CNT to graphene. This much expanded second edition reference supports knowledge discovery, production of impactful carbon research, encourages transition between research fields, and aids the formation of emergent applications. New chapters encompass recent developments in the theoretical treatments of electronic and vibrational structures, and magnetic, optical, and electrical solid-state properties, providing a vital base to research. Current and potential applications of both materials, including the prospect for large-scale synthesis of graphene, biological structures, and flexible electronics, are also critically discussed. Updated discussion of properties, structure, and morphology of biological and flexible electronic applications aids fundamental knowledge discovery Innovative parallel focus on nanotubes and graphene enables you to learn from the successes and failures of, respectively, mature and emergent partner research disciplines High-quality figures and tables on physical and mathematical applications expertly summarize key information – essential if you need quick, critically relevant data