![]() ![]() The chemical attachment of functional moieties on the reactive sites of graphitic nanostructures is determined by a number of characterization techniques. Then, covalent reactions are presumed to occur preferentially at the graphene edges and CNT tips. In graphene, however, the edges are usually considered the most reactive sites as only a few defects are observed on the highly crystalline lattice. In fullerenes and CNTs, the curvature has been put in relation with an enhanced reactivity namely, the reactivity increases with increasing degree of curvature. The main characteristic associated with most carbon nanomaterials is the presence of pentagons and heptagons in a predominantly hexagonal carbon network leading to positive and/or negative curvature. Thus, understanding carbon nanostructures’ chemical reactivity is of paramount importance in material design. In this direction, surface chemical functionalization provides an effective strategy to regulate the interface between carbon nanostructures and other materials, compounds or molecules. ![]() ![]() To a large extent, the surface properties like hydrophobicity, aromatic stacking and surface topology from the structural to the atomic level direct the performance and functionality of carbon nanostructures in composite materials and in complex interacting systems, i.e. ![]() Individual CNT and graphene sheets possess high surface areas, flexibility, electrical and thermal conductivities, properties not observed in bundles of CNTs or in graphite nanocrystals. As produced, large intermolecular forces maintain pristine carbon nanostructures forming aggregates, making the incorporation of their remarkable properties in composites challenging. This methodology, in combination with other characterization analysis, is expected to improve the design of hierarchical interfaces by the spatial localization of the functionalities responsible for colloidal stabilization in solvents with different polarities, different from their homogeneous incorporation into different matrices.Äuring the last decades the insertion of the fascinating chemical and physical properties of one-dimensional carbon nanotubes (CNTs) and two-dimensional graphene in functional materials has attracted enormous interest. The identification of the functionalities occurs in colloidal dispersions by using gold nanoparticles (AuNPs) as discriminating markers by molecular recognition or by the direct growth of AuNPs on the oxygenated moieties. In this work, we present a straightforward methodology to visualize by transmission electron microscopy the functional moieties covalently attached to the carbon network in carbon nanotubes and graphene. However, the determination of the structural conformation of functionalized nanostructures remains a difficult task. By a combination of different characterization techniques, such as high-resolution X-ray photo-spectroscopy, thermogravimetric analysis, Raman spectroscopy, UV-vis-nIR, and fluorescence spectroscopies, it is possible to identify and quantify the functional moieties covalently attached to the carbon frame. This approach resulted in the construction of tailored chemical interfaces facilitating incorporation of nanocarbons. In the search for the integration of carbon nanostructures in composite and functional materials, covalent organic reactions are successfully performed. ![]()
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