Intercalates applications

Orthorhombic crystalline vanadium pentoxide is a typical intercalation compound as a result of its layered structure, see Fig. 5.2, which finds widespread use in lithium ion intercalation applications such as electrochromic cells [17], high energy density batteries [18], supercapacitors [19], and sensors [20], since it offers the essential advantages of low cost, abundant availability, easy synthesis, and high intercalation densities [15, 16]. 

As mentioned above, employment of MWCNT for field emitter will be one of the most important applications of MWCNT. For this purpose, MWCNT is prepared by the chemical purification process [30,38], in which graphite debris and nanoparticles are removed by oxidation with the aid of CuCl2 intercalation [38]. Purified MWCNT is obtained in the form of black and thin "mat" (a flake with thickness of ca. a few hundreds of [im). Figure 7 shows a typical transmission electron microscope (TEM) picture of MWCNT with an open end, which reveals that a cap is etched off and the central cavity is exposed. 

After briefly introducing the main electronic features of CNTs (Sec. 2) and some general aspects of electronic conduction and transmission (Sec.. 1), we will show how complex electrical measurements to perform on such tiny entities are (Sec. 4). Then we will present the main experimental results obtained on the electrical resistivity of MWCNT and SWCNT and the very recent data relative to the thermopower of SWCNT bundles (Sec. 5). We will also discuss the effect of intercalation on the electrical resistivity of SWCNT bundles (Sec. 6). Finally, we will present some potential applications (Sec. 7). 

In conclusion, wc have shown the interesting information which one can get from electrical resistivity measurements on SWCNT and MWCNT and the exciting applications which can be derived. MWCNTs behave as an ultimate carbon fibre revealing specific 2D quantum transport features at low temperatures weak localisation and universal conductance fluctuations. SWCNTs behave as pure quantum wires which, if limited in length, reduce to quantum dots. Thus, each type of CNT has its own features which are strongly dependent on the dimensionality of the electronic gas. We have also briefly discussed the very recent experimental results obtained on the thermopower of SWCNT bundles and the effect of intercalation on the electrical resistivity of these systems. 

Tanuma, S., Synthesis and structure of quasi-one-dimensional carbon crystal carbolite and intercalation with alkali metals and halogens. In Supercarbon, Synthesis, Properties and Applications, ed. S. Yoshimura and R. P. H. Chang, Springer-Verlag, Heidelberg, 1998, pp. 120 127. 

Next, let us look at modification of CNTs. There are many approaches to modifying the electronic structure of CNTs oxidation [39], doping (intercalation) [69], filling [70] and substitution by hetero elements like boron and nitrogen atoms [71,72]. There have been few studies on the application of these CNTs but it will be interesting to study applications as well as electronic properties. 

An example of the modular preparation of the cyclophane 3 from the substituted bipyridine 2 and a general tripeptide 1 is shown in Scheme 3-3. The host molecule 3 contains a pre-organized binding pocket. The overall basicity of such molecules also facilitates their intercalation within the lamellas of acidic zirconium phosphate, thus making this chemistry well suited for the desired application. 

This is the most widely used naturally occurring rubber. The literature search shows that many research groups have prepared nanocomposites based on this rubber [29-32]. Varghese and Karger-Kocsis have prepared natural rubber (NR)-based nanocomposites by melt-intercalation method, which is very useful for practical application. In their study, they have found increase in stiffness, elongation, mechanical strength, and storage modulus. Various minerals like MMT, bentonite, and hectorite have been used. 

Rubber-clay nanocomposites are particularly attractive for potential applications where enhanced barrier properties are desired. Organoclays for rubber intercalation were prepared... 

Metal chalcogenides, apart from their technological significance in industrial applications, have played an important role in the development of new synthetic concepts and methods in the area of solid-state chemistry. A great example is alkali metal intercalation into TiS2 (Chap. 6) first reported three decades ago, which highlighted the then-novel synthetic approach called soft chemistry chimie douce). This low-temperature process allows for new compounds to be obtained while retaining the structural framework of the precursor. Related to this concept is the... 

Kanehori K, Matsumoto K, Miyauchi K, Kudo T (1983) Thin film solid electrolyte and its application to secondary Lithium cell. Solid State Ionics 9-10 1445-1448 Py MA, Haering RR (1983) Structural destabilization induced by lithium intercalation in M0S2 and related compounds. Can J Phys 61 76-84... 

A wider application of ruthenium oxide capacitors is hindered by the high cost of ruthenium oxide. Attempts have been reported, therefore, to substitute ruthenium oxide with other, cheaper materials capable of intercalation and deintercalation of hydrogen and/or other ions. Promising results with pseudocapacities of about 100 F/g have been obtained with the mixed oxides of ruthenium and vanadium and also with mixed oxides on the basis of manganese oxide. 

At present, intercalation compounds are used widely in various electrochemical devices (batteries, fuel cells, electrochromic devices, etc.). At the same time, many fundamental problems in this field do not yet have an explanation (e.g., the influence of ion solvation, the influence of defects in the host structure and/or in the host stoichiometry on the kinetic and thermodynamic properties of intercalation compounds). Optimization of the host stoichiometry of high-voltage intercalation compounds into oxide host materials is of prime importance for their practical application. Intercalation processes into organic polymer host materials are discussed in Chapter 26. 

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