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In this chapter, our purpose is to introduce carbon materials, situating the nanotubes inside this . We aim at giving the reader the basic notions on carbon materials structural and physical properties, necessary for the understanding of the following chapters. The introductory section gives a historical background about the peculiar carbon element and the numerous carbon materials which have been identified up to now. Then in a second part a classical thermodynamic approach is presented to describe the crystalline and non-crystalline forms of carbon, up to fullerenes and nanotubes. It is shown that the choice of the processing ways, including the crucial role played by the temperature, is fundamental to control the final type of material. In particular the different processes to prepare non-crystalline graphitic carbons are described in Sect. 1.3. Based on the texture symmetries different types of classical carbon materials are presented in relation with their numerous industrial applications. Then a general introduction is given concerning mainly the transport properties of the crystalline forms, including the intercalation compounds, but also their ‘avatars’ as pregraphitic carbons. In a final part, this panorama, which is going from the classical forms to the more molecular ones including nanotubes, is completed by the presentation of similar compounds. Starting from neighboring elements in the periodic classification we show that doped carbons and parent compounds present a similar polymorphism which enlarges this general introduction.

In this chapter, our purpose is to present how carbon nanotubes are synthesized and how their formation and growth can be studied, understood and modeled. We give an overview of the different synthesis methods, which can be classi fied into two main categories according to the synthesis temperature. We include a review of the CVD synthesis of carbon filaments, as an introduction to that of nanotubes.

Much of our knowledge on the atomic structure of a material system comes from experiments based on the interaction of radiation with the atoms. The present chapter is devoted to interactions of radiations in a broad sense – electromagnetic waves and particles (electrons or neutrons) – with matter. Each elementary interaction process is called a scattering. An elastic scattering process can only modify the direction of the wave vector of the radiation, not its energy. A well-known example is the Rayleigh scattering on an electromagnetic wave by a polarizable object, which must be small on the wavelength scale. Then, the incident wave excites an electric dipole in the object, which oscillates in time with the frequency of the incident electric field and radiates a wave in all the directions. This radiated wave is the scattered radiation.

This chapter is devoted to a discussion of the electronic structure of carbon and other nanotubes. It begins with a very general description of sp electronic states based on the tight-binding or Hückel approximation. This is sufficient to capture many basic electronic properties of single-walled nanotubes. This is followed by a more detailed analysis of the properties of carbon nanotubes, which is necessary when considering curvature effects, multi-walled nanotubes, bundles, etc. Although much less studied, other non-carbon nanotubes deserve also some attention: because of their ionic character boron nitride nanotubes and other mixed nanotubes offer in particular the opportunity of varying the electronic gap. This is described in a following section. The possibility of monitoring the electronic structure of carbon nanotubes as in the case of graphite, by intercalation and charge transfer are also investigated. Finally an extensive review on field emission is presented.

In a spectroscopy experiment, radiation is used as a probe of the properties of a system. A typical experiment of spectroscopy is schematized in Fig. 5.1. The source (probe) can be X-rays, laser light (visible and infrared radiations), neutrons, electrons, … . A monochromatic radiation is obtained by using a relevant monochromator device. As long as the response of the material to the radiation is linear, the function which describes the interaction is called the response function and it can be calculated using the linear response model. This response function (, ) relates the field associated with the source, (, ) to the response of the system, (, )

In this chapter, we first review the fundamental theoretical concepts of mesoscopic transport for low-dimensional systems and disordered materials. Emphasis is put on the Landauer formulation of electronic transmission, weak localization and Aharonov-Bohm phenomena, as well as Coulomb interactions through screening effects and Luttinger liquid model. A pedagogical effort is made to present the currently established physics of quantum conduction in some analytical detail, enabling the reader to further deepen the understanding of more specialized literature. In a subsequent part, the main theoretical features of quantum transport in carbon nanotubes are elaborated, mostly within the non-interacting electron regime, that is to date less controversial. The experimental part starts with a discussion of the commonly employed measurement techniques. Several transport experiments are then analyzed, with a particular focus on device-oriented aspects (field effect, Schottky barriers, etc). Finally, the main physical properties of nanotube-based composites are outlined, followed by a presentation of our current understanding of thermal properties of carbon tubules.

After introducing some basic notions on mechanical properties of solids, focusing particularly on polymers, properties of a single nanotube will be treated, before those of nanotube-containing composites. This chapter aims to show why nanotube-based composites are promising materials, how their properties could be improved, and what the main problems are currently encountered by the community. The use of nanotubes in composites, first delayed by the lack of cheap products available in large quantities, is now expanding and we can reasonably believe that new important applications will soon appear. In particular, significant progress have been made in making macroscopic fibers of aligned nanotubes.

Since their discovery, carbon nanotubes have been proposed for a number of applications, such as gas storage, reinforcement of composites, electrochemical energy storage, catalyst support, where the nanotexture and surface functionality are of fundamental importance. With regard to surface properties, this new form of carbon is not significantly different from the other classical carbon forms (carbon fibers, pyrolytic carbon, graphite, activated carbons, …) which are also constituted of graphitic carbon layers. Therefore, this chapter aims in its first part at presenting the porous properties and surface functionality of carbon materials and the techniques to control or modify these parameters. However, due to their nanoscale size morphology and inner cavity which can host various species, carbon nanotubes are expected to present specific properties. Mats of highly entangled nanotubes offer an open network of mesopores which favors the access of molecules and ions to the active surface. The second part of this chapter will be focused on the presentation of some specific chemical and electrochemical properties of carbon nanotubes. Filling of nanotubes and in-situ chemistry in the cavity will be documented. Application of carbon nanotubes as lithium battery or supercapacitor electrode materials will be critically discussed by comparison with other kinds of nanostructured carbons.