In-flight size classification of carbon nanotubes by gas phase electrophoresis

We demonstrate the use of gas phase electrophoresis to size classify CNTs grown in a continuous aerosol process. The separation process occurs at atmospheric pressure and involves electrostatic mobility separation which classifies fibres on the basis of equivalent projected surface area. This implies that one can, for diameter-controlled CNTs, obtain an on-the-fly determination of the CNT length distribution during CNT synthesis, or alternatively have a method for producing size separated CNTs. The method should be generic to any fibre based material.