Nanocarbon materials have become increasingly popular as nanostructured fillers in composites and more recently as functional components in the new class of hybrid materials owing to their outstanding structural, electrical, and physical features. Thus, it is crucial to understand how these properties can be realized in composites and hybrids. In order to obtain better performance of these nanocarbon materials in multi-component systems, plenty of techniques have been developed to solve practical problems in handling of nanocarbons, such as self-aggregation and restacking phenomena due to strong van der Waals forces, which are major hurdle that limits individual nanocarbons from realizing their full potential in assembled composite and macroscopic materials.Therefore, thestructure control of nanocarbons can give a solution to achieve stable dispersion state and effective network structure during process and final structure, resulting in possibilities to tailored nano-structures/assemblies, and novel functionalities that go beyond the intrinsic properties.
Here I present a facile method to prepare surface functionalized multi-walled carbon nanotubes by applying direct $\gamma$-ray irradiation under oxygen atmosphere. The modified nanotubes with oxygen containing functional groups showed enhanced interaction with polymer matrix, resulting in improvement of morphological, electrical, and rheological properties of composites.
Additionally, on the basis of using chemically derived graphenes, I introduce self-assembled structures in the form of free-standing paper-like structures with structure-controlled restacking of individual graphene sheets; 1) highly flexible wrinkled graphene paper and 2) 3D macroporous reduced graphene oxide film. These fascinating graphene-based structures may be a promising candidate as an electrode material for Lithium-based rechargeable batteries, also open up numerous opportunities for the application of graphene in macroscopic assembled structures.