Abstract: The invention relates to a method for depositing nanometric filamentary structures. The method comprises passing a gaseous phase comprising the nanometric filamentary structures through a space defined between at least two electrodes generating an electric field, for depositing the nanometric filamentary structures on at least one of the electrodes; and at least substantially preventing the deposited nanometric filamentary structures from bridging the electrodes during the deposition. The invention also relates to an apparatus for depositing nanometric filamentary structures as well as to methods and apparatuses for monitoring the production of nanometric filamentary structures.

Abstract: There is provided a method for purifying carbon filamentary structures contaminated with magnetic metal particles. The method comprises submitting a gaseous phase comprising said carbon filamentary structures contaminated with magnetic metal particles, to an inhomogeneous magnetic field for at least partially trapping said magnetic metal particles, thereby reducing the proportion of said magnetic metal particles present in said gaseous phase. The method is particularly useful for purifying carbon filamentary structures such as multi-wall carbon nanotubes, single-wall carbon nanotubes or carbon fibers. An apparatus for purifying such carbon filamentary structures contaminated with magnetic metal particles is also provided.

Abstract: The invention relates to a macroscopic assembly of nanometric filamentary structures. The macroscopic assembly comprises a plurality of microscopic assemblies substantially aligned in a same direction and connected together. Each of the microscopic assemblies comprises a plurality of members defining a plurality of spaces therebetween. Each of the members comprises a nanometric filamentary structure or a bundle of nanometric filamentary structures, wherein the macroscopic assembly has a density of less than 8 mg/cm3. The is also provided a method for prerparing such a macroscopic assembly.

Abstract: Carbon nanotubes are formed on carbon paper by first depositing a metal catalyst on the carbon paper, and passing a feedstock gas containing a source of carbon over the substrate while applying an electrical current thereto to heat the substrate sufficiently to generate a reaction between the catalyst and the feedstock gas. Alternatively, inert gas under pressure is passed through a tubular metal cathode while passing an electric current through the cathode to produce a plasma of fine catalyst particles which are deposited on a porous carbon substrate, and a feedstock gas containing a source of carbon is passed over the substrate to cause a reaction between the catalyst and the carbon source resulting in the formation of carbon nanotubes.

Abstract: Carbon nanotubes are formed on carbon paper by first depositing a metal catalyst on the carbon paper, and passing a feedstock gas containing a source of carbon over the substrate while applying an electrical current thereto to heat the substrate sufficiently to generate a reaction between the catalyst and the feedstock gas. Alternatively, inert gas under pressure is passed through a tubular metal cathode while passing an electric current through the cathode to produce a plasma of fine catalyst particles which are deposited on a porous carbon substrate, and a feedstock gas containing a source of carbon is passed over the substrate to cause a reaction between the catalyst and the carbon source resulting in the formation of carbon nanotubes.