Abstract: A catalyst material for preparing nanotubes, especially carbon nanotubes, said material being in the form of solid particles, said particles including a porous substrate supporting two superposed catalytic layers, a first layer, directly positioned on the substrate, including at least one transition metal from column VIB of the Periodic Table, preferably molybdenum, and a second catalytic layer, positioned on the first layer, comprising iron. Also, a process for preparing same and to a process for the synthesis of nanotubes using this catalyst material.

Abstract: The present invention relates to a device for providing vapors of at least one solid precursor intended to supply a physico-chemical processing device, comprising an enclosure capable of containing particles of the solid precursor and comprising an inlet and an outlet, the outlet being intended to be connected to the physico-chemical processing device; and means for circulating a gas between the inlet and the outlet to put the particles of the solid precursor in the form of a fluidized bed, and to convey to the outlet vapors of the solid precursor.