Download or read book Synthesis and Characterization of Nitrogen Boron Chlorine and Fluorine Doped Carbon Nanotubes written by Adeniyi Olugbenga Osikoya and published by . This book was released on 2013 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes (CNTs) doped with nitrogen, boron, chlorine and fluorine have been synthesized in a catalytic chemical vapour deposition (CCVD) reactor at 700 and 800 °C, using cobalt and silver as catalysts supported on magnesium oxide. The synthesized carbon nanotubes were characterized by Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction spectroscopy (XRD), Thermogravimetric analysis (TGA) and Energy dispersive spectroscopy (EDS). Carbon nanotubes doped with nitrogen were found to have internal bamboo shaped structures in the TEM results. Carbon nanotubes doped with boron were also found to have compartmentalized internal structures with narrower inner diameter compared to the outer diameter. SEM characterization shows that carbon nanotubes doped with chlorine have tapered or spike-like external morphology. While fluorine doped carbon nanotubes shows the formation of a lot of carbon nanospheres and, amorphous carbon in addition to the formation of tubular structures with rough and grainy-like external morphology.
Download or read book Boron and Nitrogen doped Carbon Nanotubes written by Godfrey Kamitha Keru and published by . This book was released on 2015 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis of Nitrogen doped Carbon Nanotubes written by Kambiz Chizari and published by . This book was released on 2011 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the discovery of carbon nanotubes (CNT) in 1991, a lot of efforts have been done in order to find out their intrinsic properties and their possible applications. One of the most efficient methods used for tuning its physical and chemical properties is doping CNTs by nitrogen or boron. The aim of this work deals with the synthesis of nitrogen-doped carbon nanotubes (N-CNTs) and with the study of the catalytic performance of this material either as catalyst support or as a metal-free catalyst. The influence of the different synthesis parameters on the physical and chemical properties of the N-CNTs was investigated. Afterwards, the N-CNTs were used as catalyst support for the hydrogenation of cinnamaldehyde and its catalytic performance was compared to that obtained on the undoped CNTs. It was shown that N-CNTs synthesized in different conditions lead to different catalytic performances which was mainly linked with the nature of the incorporated nitrogen species. The N-CNTs were also employed as a metal-free catalyst for the selective oxidation of H2S into elemental sulfur and the results are discussed within this thesis. Recently 2D carbon material, namely graphene, has received a great interest due to its special physical properties. The previous investigations on the other graphitic material such as carbon nanotubes facilitate the understanding of the properties and behavior of this material. In this thesis we also worked on the synthesis of the few-layer graphene (FLG), using microwave irradiations. A preliminary study has also done on the nitrogen-doping of this material by microwave treatment on the expanded graphite dispersed in ammonium hydroxide. The FLGs were used as a catalyst support for the hydrogenation of cinnamaldehyde and its catalytic performance is compared to other graphitic materials such as natural graphite, expanded graphite and carbon nanotubes.
Download or read book Carbon Nanotubes and Related Structures written by Dirk M. Guldi and published by John Wiley & Sons. This book was released on 2010-01-26 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by the most prominent experts and pioneers in the field, this ready reference combines fundamental research, recent breakthroughs and real-life applications in one well-organized treatise. As such, both newcomers and established researchers will find here a wide range of current methods for producing and characterizing carbon nanotubes using imaging as well as spectroscopic techniques. One major part of this thorough overview is devoted to the controlled chemical functionalization of carbon nanotubes, covering intriguing applications in photovoltaics, organic electronics and materials design. The latest research on novel carbon-derived structures, such as graphene, nanoonions and carbon pea pods, round off the book.
Download or read book Doping of Carbon Nanotubes written by Sergey Bulyarskiy and published by Springer. This book was released on 2017-07-01 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the control of electronic properties of carbon nanotubes. It presents thermodynamic calculations of the formation of impurities and defects in the interaction of nanotubes with hydrogen, oxygen, nitrogen and boron, based on theoretical models of the formation of defects in carbon nanotubes. It is shown that doping and adsorption lead to changes in the electronic structure of the tubes as well as to the appearance of impurity states in the HOMO-LUMO gap. The book presents examples of specific calculations for doping of carbon nanotubes with oxygen, hydrogen, nitrogen and boron, together with numerous experimental results and a comparison with the author’s thermodynamic calculations. Possible directions of the technological processes of optimization are pointed out, as well as the perspectives of p-n-transition creation with the help of carbon nanotube arrays. The results presented were derived from the physics of the processes and a theoretical model of the technological processes. Though a wealth of empirical information on doping nanotubes has been accumulated in the scientific literature, what is lacking is a theoretical model for their analysis. As such, the book develops a thermodynamic model of the self-organization of structural elements in multicomponent systems – including carbon nanotubes, clusters and precipitates in condensed matter – and subsequently adapts it to the doping of carbon nanotubes. This approach allows readers to gain a far deeper understanding of the processes of doping carbon nanotubes.
Download or read book Synthesis And Characterization Of Silicon Doped Single Walled Carbon Nanotubes written by John Slimak and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon doping of carbon nanotubes produces an isovalent structure, unlike that of similar boron or nitrogen doped tubes which display p- and n- characteristics, and causes unique structural changes to the nanotubes, altering the properties of both single tubes and bulk materials. Silicon doped single-walled nanotubes were prepared by chemical vapor deposition of ethanol vapor with catalytic ferrocene and methoxytrimethylsilane dopant. The material was characterized by Raman spectroscopy to determine the success of the synthesis and also to probe the diameter of the nanotubes; the presence of subsitutional silicon atoms in the nanotube lattice create a preference for lower diameter tubes, a change that is easily observable through the radial breathing mode of the doped nanotubes.
Download or read book Preparation and Characterization of Nitrogen Doped Carbon Nanotube Electrode Materials written by Stephen Maldonado and published by . This book was released on 2006 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes the preparation and characterization of nitrogen doped carbon nanotube films by a chemical vapor deposition (CVD) process. Thorough description of the preparation method is given. A variety of techniques are used to demonstrate the relationship between the physicochemical properties and electrochemical properties of nitrogen doped carbon nanotubes, shedding insight to the influence of nitrogen doping on observed electrocatalysis phenomena. Chapter 1 comprises a general overview of the presented material and scope of the work. Chapter 2 details the CVD preparation of nitrogen doped carbon nanotubes. Scanning electron microscopy, thermal gravimetric analysis, and x-ray photoelectron spectroscopy are used to demonstrate the degree of control afforded by the CVD process over the resultant properties of the prepared carbon nanotubes. The direct preparation of carbon nanotube films on a current collector is shown. Chapter 3 consists of a thorough characterization and comparison of nitrogen doped carbon nanotubes and non-doped carbon nanotubes. Transmission electron microscopy, thermal gravimetric analysis, and Raman spectroscopy demonstrate the increased disorder caused by nitrogen doping into the graphitic lattice structure of carbon nanotubes. X-ray photoelectron spectroscopy highlights the existence of multiple carbon-nitrogen surface functionalities that change in relative abundance as the nitrogen content is varied. Titration analyses indicate that nitrogen doped carbon nanotubes are basic and acquire a cationic surface charge in solutions of neutral pH. Chapter 4 presents a collection of voltammetric responses of several outer-sphere and inner-sphere redox probes. The similarities and differences between the responses at non-doped carbon nanotube electrodes and nitrogen doped carbon nanotube electrodes are noted and discussed in the context of the conclusions of the physical characterizations. A detailed mechanistic analysis of the O2 reduction process at nitrogen doped carbon nanotube electrodes is presented. Chapter 5 details continuing work with carbon nanotube materials for fundamental and applied studies.
Download or read book Synthesis Characterization and Chemical Functionalization of Nitrogen Doped Carbon Nanotubes for the Application in Gas and Bio sensors written by Yangxi Fu and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitrogen Doped Carbon Nanotubes written by S. van Dommele and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Carbon Nanotubes From Basic Research to Nanotechnology written by Valentin N. Popov and published by Springer Science & Business Media. This book was released on 2006-04-04 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book comprises reviews on various topics of carbon nanotube research from specialists in the field, together with reports on on-going research. Both are intended to give a detailed picture of the remarkable properties of these one-dimensional nanostructures. Particular attention is paid to the synthesis, characterization, properties, and application of nanotubes. The book will be an indispensable introduction for the newcomers in the field as well as a valuable update for researchers in the field, for it contains the most recent developments.
Download or read book Synthesis Characterization and Fabrication of Boron Nitride and Carbon Nanomaterials Their Applications and the Extended Pressure Inductively Coupled Plasma Synthesis of Boron Nitride Nanotubes written by Aidin Fathalizadeh and published by . This book was released on 2016 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoscale materials made of carbon, boron, and nitrogen, namely BCN nanostructures, exhibit many remarkable properties making them uniquely suitable for a host of applications. Boron nitride (BN) and carbon (C) nanomaterials are structurally similar. The forms studied here originate from a two-dimensional hexagonally arranged structure of sp2 bonded atoms. These nanomaterials exhibit extraordinary mechanical and thermal properties. However, the unique chemical compositions of carbon and boron nitride result in differing electrical, chemical, biological, and optical properties. In this work, we explore the single layer sheets of sp2 bonded carbon (graphene), and their cylindrical forms (nanotubes) of carbon and boron nitride. In the first part of this work, we look at carbon based nanomaterials. In Chapter 2, the electron field emission properties of carbon nanotubes (CNTs) and their implementation as nanoelectromechanical oscillators in an integrated device will be discussed. We show a technique hereby a single CNT is attached to a probe tip and its electron field emission characterized. We then delve into the fabrication of a field emitting CNT oscillator based integrated device using a silicon nitride membrane support. We then present the electron field emission capabilities of these devices and discuss their potential use for detection of nuclear magnetic resonance (NMR) signals. Graphene is the subject of study in Chapter 3. We begin by extensively examining the synthesis of graphene using a chemical vapor deposition (CVD) process, ultimately establishing techniques to control graphene domain size, shape, and number of layers. We then discuss the application of the single-atom thick, but ultra-mechanically strong graphene as a capping layer to trap solutions in a custom fabricated silicon nitride membrane to enable transmission electron microscopy (TEM) of liquid environments. In this manner, the volume and position of liquid cells for electron microscopy can be precisely controlled and enable atomic resolution of encapsulated particles. In the second portion of this work, we investigate boron nitride nanostructures and in particular nanotubes. In Chapter 4, we present the successful development and operation of a high-throughput, scalable BN nanostructures synthesis process whereby precursor materials are directly and continuously injected into a novel high-temperature, Extended-Pressure Inductively-Coupled plasma system (EPIC). The system can be operated in a near-continuous fashion and has a record output of over 35 g/hour for pure, highly crystalline boron nitride nanotubes (BNNTs). We also report the results of numerous runs exploring the wide range of operating parameters capable with the EPIC system. In Chapter 5, we examine the impurities present in as-synthesized BNNT materials. Several methods of sample purification are then investigated. These include chemical oxidation, using both gas and liquid phase based methods, as well as physical separation techniques. The large scale synthesis of BNNTs has opened the door for further studies and applications. In Chapter 6, we report a novel wet-chemistry based route to fill in the inner cores of BNNTs with metals. For the first time, various metals are loaded inside of BNNTs, forming a plethora of structures (such as rods, short nanocrystals, and nanowires), using a solution-based method. We are also able to initiate and observe dynamics of the metallic nanoparticles, including their movement, splitting, and fusing, within a BNNT.
Download or read book Nitrogen doped Carbon Nanotubes written by Lucy Mudiwo Ombaka and published by . This book was released on 2015 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Characterization of Pure and Nitrogen Doped Carbon Nanostructures written by Abhay Pratap Singh and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physiochemical Properties of Boron and Nitrogen doped Carbon Nanotubes titania Nanocomposites for Dye sensitised Solar Cells written by Samantha Ndlovu and published by . This book was released on 2017 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Chemistry and Structure of Boron doped Carbon Nanotubes and Nanofibers written by Ling Wang and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Characterization of Titanium Dioxide Nanotubes on Fluorine doped Tin Oxide FTO Glass Substrate Using Electro anodization Technique written by Simcelile Zinya and published by . This book was released on 2017 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Synthesis and Characterization of Several Boron nitrogen Compounds written by Brian Washburn and published by . This book was released on 1973 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
