a1 Centre d’élaboration des Matériaux et d’Etudes Structurales, UPR-8011 CNRS, F-31055 Toulouse cedex 04, France
a2 Centre Interuniversitaire de Recherche et d’Innovation sur les Matériaux, UMR-5085 CNRS, F-31062 Toulouse, France
a3 Centre d’élaboration des Matériaux et d’Etudes Structurales, UPR-8011 CNRS, F-31055 Toulouse cedex 04, France
We introduce the concept of meta-nanotubes, among which are hybrid carbon nanotubes (X@CNTs), which are CNTs whose hollow core is filled—fully or partially—with foreign atoms, molecules, or compounds. The article focuses on the latter, describing their potential interest and the various ways currently available to synthesize them, while providing examples of the resulting materials mainly taken from the author’s works but also from literature, as characterized by means of high-resolution microscopy and related techniques. We discuss advantages and drawbacks of the various synthesis routes to help willing scientists and engineers to define a strategy for X@CNT synthesis with respect to their specific goals and expectations. Some examples of peculiar properties and behaviors of X@CNTs will be provided as well, although such related investigations are still scarcely reported because we are dealing with quite new nanomaterials.
(Received June 30 2006)
(Accepted September 07 2006)
(Online publication March 03 2011)