The remarkable properties of single-walled carbon nanotubes (SWNTs) and potential
applications are hindered by current solution-phase processing strategies. The initial dissolution
of SWNTs remains a fundamental challenge, reliant on aggressive chemistry or ultrasonication and
lengthy ultracentrifugation. In this thesis, a simple non-aqueous electrochemical reduction process
that leads to spontaneous dissolution of individualised SWNTs from raw, unprocessed powders is
outlined. The intrinsic electrochemical stability and conductivity of these nanoparticles allows
their electrochemical dissolution from a pure SWNT cathode to form solutions of well-defined
nanoparticle anions with characteristic charge density. Other than a reversible change in
redox/solvation state, there is no obvious chemical functionalisation of the structure, suggesting
an analogy to conventional atomic electrochemical dissolution. The heterogeneity of as-synthesised
SWNT samples leads to the sequential dissolution of distinct fractions over time. Initial
preferential dissolution of defective nanotubes and carbonaceous debris provides a simple,
non-destructive means to purify raw materials without recourse to the usual, damaging, competitive
oxidation reactions. During early stage developments, the process showed remarkable affinity for
dissolving metallic SWNTs, providing a potentially scalable route for separation by electronic
character, vital for many applications. However, selectivity was lost with significantly increased
process yields (complete dissolution) following several optimisations. Subsequently, the
electrochemical deposition of SWNTs is proposed as a new route to selectively plate specific SWNT
species and avoid unwanted functionalisations that occur when exposing reduced SWNTs to different
atmospheres. Finally, the extension of electrochemical processing to related materials including
activated and graphitic nanocarbons, metallic and metal chalcogenide nanomaterials was also
investigated, with great promise for the development of
new applications.