Dispersable pastes comprising single-walled carbon nanotubes (SWNT) in water or in an organic solvent are prepared. The method of preparing the dispersable pastes comprises in general the following steps: a) removal of the catalyst used during the synthesis of SWNT; b) while the SWNT are still wet, addition of the appropriate amount of solvent, in a solvent/SWNT ratio which preferably varies between 30:1 and 100:1, depending on the desired viscosity of the paste; and c) high-energy horn sonication with a dismembrator probe.The resulting pastes are suitable for easy redispersion in solvents and incorporation in various matrices such as polymers. They are also suitable to be impregnated with metal precursors such as noble metal compounds for example, Pt. Appropriate drying and thermal treatments of the impregnated material produce metal-SWNT composites in which small metal clusters can be uniformly dispersed over the nanotube surface. These metal-SWNT composites may find applications as catalysts as well as electrodes for fuel cells, batteries, and capacitors.