Plasma-Enhanced Atmospheric Pressure Spray Pyrolysis System for the Production of Few Walls Carbon Nanotubes

Spray pyrolysis is a recognized technique for the preparation of multi-walled Carbon Nano-Tubes (CNTs). Likewise, gas-phase plasma synthesis has the best potential to produce nanoparticles with narrow sized distribution in short times. Here we present a combination of both concepts to design an atmospheric-pressure plasma reactor in a configuration which can be scaled for massive production of few-walls CNTs. This hybrid setup uses a pneumatic nebulizer which produces an aerosol from a solution of toluene (the carbon source) in the presence of ferrocene (the catalyst). The mist goes toward the plasma zone, which is generated by a DC-soldering torch. The plasma effect is to reduce the droplet size of the nebulizer. By this mean the agglomeration of Fe nanoparticles is reduced and consequently, the number of walls and diameter of CNTs are decreased.