Composite Systems and Materials

Nanotubes synthesis reactor by continuous laser vaporization

Synthesis reactor by continuous laser vaporization
left: carbon nanotubes	right: boron nitride nanotubes

In the frame of the Federator Research Project « NANOTECHNIA », the Composites Systems and Materials Department studies the synthesis of carbon and boron nitride nanotubes by continuous laser vaporization process. Two reactors are located in the Palaiseau center.

General diagram of a synthesis reactor

The process consists in vaporizing a cylindrical target (compacted mix of carbon and metal catalysts, or boron nitride rod) by the mean of a continuous wave CO₂ laser of 1500 Watts. See video clips...

The objective is to analyse the synthesis conditions of the single-wall nanotubes of carbon or boron nitride, and to determine the influence of the synthesis parameters such as the temperature of vaporization, the nature of the atmosphere in the reactor, the pressure and the gas flow rate.

The products obtained are observed by scanning electron microscopy and high resolution transmission electron microscopy by the Laboratory for Microstructural Investigations, which develops a model of growth of the nanotubes on the basis of these observations and theoretical calculations. In parallel, the gas flow in the reactor is modelled thanks to the computer code Mathilda-Saphyr-Diamond, developed by the Fundamental and Applied Energetics Department. The code was validated by in-situ measurements of the temperature of the gas phase by optical diagnostics (DRASC) developped by the Physics, Instrumentation and Sensing Department.

Others optical diagnostics are developed : the Laser Induced Fluorescence (LIF) for the analyse of the species present in the gas phase at the top of the target, and the Laser Induced Incandescence (LII) for the measurement of the density and the size of the particles in the gas flow. LII Measurements are taken in collaboration with a team of the DLR Stuttgart.

Among the possible applications, the use of nanotubes as reinforcement for the improvement of the compression behaviour of the organic matrix composites is studied by the Composite Systems and Materials Department.

Last Update: 5 May 2006 - © ONERA 2009 - Terms of use