Nanostructured carbon materials functionalization

Nanostructured Carbon Materials for Catalysis 24 Heterocycles from Double-Functionalized Arenes Transition Metal Catalyzed Coupling Reactions 25 Asymmetric Functionalization of C—H Bonds... 

Summarizing, noncovalent functionalization methods can be used to prepare materials with specific biological properties because they are quick, efficient and clean. In order to increase biocompatibility of carbon nanostructures, these materials now need to be integrated into living systems and to be potentially used as tissue regeneration scaffolds, prostheses or drug deliverers. 

Besides the practical application, the diversity of nanostructured carbon allotropes makes nanocarbon also an ideal model system for the investigation of structure-function correlations in heterogeneous catalysis. Nanocarbons can be tailored in terms of their hybridization state, curvature, and aspect ratio, i.e., dimensions of stacks of basic structural units (BSU), Chapters 1 and 2. The preferred exposition of two types of surfaces, which strongly differ in their physico-chemical behavior, i.e., the basal plane and prismatic edges, can be controlled. Such controlled diversity is seldom found for other materials giving carbon a unique role in this field of basic research. The focus of this chapter is set on the most prominent representatives of the... 

A relatively high reversible capacity (372mAh/g, i.e., one lithium for six carbon atoms in standard conditions) at a potential close to metallic lithium and a moderate irreversible capacity can be obtained with graphite-based anodes. A higher degree of reversible lithium insertion than in graphite, but also an important irreversible capacity, is observed with various kinds of nanostructured carbons. Therefore, an intensive research effort is focused on the optimization of the anodic carbon materials, with the objectives to enhance the reversible capacity and to reduce as much as possible the irreversible capacity and hysteresis, which are often important drawbacks of these materials. The next section will discuss the correlations between the electrochemical performance of nanostructured carbons and their nanotexture/structure and surface functionality. Taking into account the key parameters that control the electrochemical properties, some optimizations proposed in literature will be presented. 

Nanostructured wide bandgap materials functionalized with Pd or Pt are even more sensitive than their thin film counterparts because of the large surface-to-volume ratio (Lim et al, 2008 Johnson et al, 2009). 1-D semiconductor nanomaterials (such as carbon nanotubes (CNTs), Si nanowires,... 

Nanoporous carbon materials, including black carbons, functionalized carbon, nanostructured carbon, nanostructured diamond like carbon, graphene, N-doped graphene, hierarchical porous carbonaceous foams... 

Carbon occurs in many forms, and their properties, depending on each form of its special structure, make carbon a truly unique building block for nanomaterials. Nanocarbon materials are defined so that not only is their primary particle size on a nanometer scale, but also their structures and/or textures are controlled on a nanometer scale [1]. Either the nanosize or nanostructure of the carbon materials have to be deliberately controlled to govern their properties and functions [2], In the last two decades, novel... 

One-dimensional (ID) nanostructures have also been the focus of extensive studies because of their unique physical properties and potential to revolutionize broad areas of nanotechnology. First, ID nanostructures represent the smallest dimension structure that can efficiently transport electrical carriers and, thus, are ideally suited for the ubiquitous task of moving and routing charges (information) in nanoscale electronics and optoelectronics. Second, ID nanostructures can also exhibit a critical device function and thus can be exploited as both the wiring and device elements in architectures for functional nanosystems.20 In this regard, two material classes, carbon nanotubes2131 and semiconductor nanowires,32"42 have shown particular promise. 

These novel carbon nanostructures can also be modified by (a) doping, that is the addition of foreign atoms into the carbon nanostructure, (b) by the introduction of structural defects that modify the arrangement of the carbon atoms and (c) by functionalization involving covalent or noncovalent bonding with other molecules. These modifications opened up new perspectives in developing novel composite materials with different matrices (ceramic, polymer and metals). For example, polymer composites containing carbon nanostructures have attracted considerable attention due to... 

Although there have been great advances in covalent functionalization of fullerenes to obtain surface-modified fullerene derivatives or fullerene polymers, the application of these compounds in composites still remains unexplored, basically because of the low availability of these compounds [132]. However, until now, modified fullerene derivatives have been used to prepare composites with different polymers, including acrylic [133,134] or vinyl polymers [135], polystyrene [136], polyethylene [137], and polyimide [138,139], amongst others. These composite materials have found applications especially in the field of optoelectronics [140] in which the most important applications of the fullerene-polymer composites have been in the field of photovoltaic and optical-limiting materials [141]. The methods to covalently functionalize fullerenes and their application for composites or hybrid materials are very well established and they have set the foundations that later were applied to the covalent functionalization of other carbon nanostructures including CNTs and graphene. 

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