Device for the synthesis of nanoparticles by fluidized-bed chemical vapor deposition

A device for vapor deposition of chemical species on support grains of spherical or similar shape disposed in a fluidized bed, the device comprising:

• a first chamber including a fluidized bed in which a funnel-shaped fluidizer element is housed to receive support grains of spherical or similar shape;
• a second chamber in fluid flow connection with the first chamber to deliver precursors in a vapor phase of chemical species to be deposited on the support grains and to convey a fluidizing gas towards the first chamber, said second chamber having a pipe to deliver precursors in a vapor phase of chemical species to be deposited on the support grains, said pipe passing through the second chamber and being leaktight relative to the second chamber and further presenting a gas-expansion pre-chamber;
• and
• a distributor flute at an inlet to the fluidizer element to control distribution of the vapor phase precursors and of the fluidizing gas within the fluidizer element, said distributor flute comprising an inner pipe to convey the precursors in the vapor phase from the pipe passing through the second chamber within the fluidizer element and arranged relative to the fluidizer element in such a manner that the fluidizing gases coming from the second chamber pass between the outer portion of the distributor flute and the fluidizer element, said fluidizer including one or more outer grooves, the outer groove or each of the outer grooves including a first portion vertically oriented along the longitudinal axis of the flute and parallel to said axis and a second portion winding helically around said longitudinal axis to generate a fluidizing gas vortex within the first chamber.