Separating Metallic and Semiconductor SWNTS with sinusoidal dipole-inducing magnetic fields

摘要

A process of sorting metallic single wall carbon nanotubes (SWNTs) from semiconducting types by disposing the SWNTs in a dilute fluid, exposing the SWNTs to a dipole-inducing magnetic field which induces magnetic dipoles in the SWNTs so that a strength of a dipole depends on a conductivity of the SWNT containing the dipole, orienting the metallic SWNTs, and exposing the SWNTs to a magnetic field with a spatial gradient so that the oriented metallic SWNTs drift in the magnetic field gradient and thereby becomes spatially separated from the semiconducting SWNTs. An apparatus for the process of sorting SWNTs is disclosed.

主权项

1. A process of sorting metallic single wall carbon nanotubes (SWNTs) from semiconducting SWNTs, comprising:
A. disposing the metallic SWNTs and the semiconducting SWNTs in a dilute fluid; B. applying a varying dipole-inducing magnetic field to the metallic SWNTs and the semiconducting SWNTs in the dilute fluid, including varying the dipole-inducing magnetic field with time so as alternately increase the dipole-inducing magnetic field with time and decrease the dipole-inducing magnetic field with time, and in which the applying a varying dipole-inducing magnetic field includes: i. providing an upper dipole-inducing electromagnetic coil and a lower dipole-inducing magnetic coil; ii. applying to the upper dipole-inducing electromagnetic coil a current with a triangular profile waveform; and iii. applying to the lower dipole-inducing electromagnetic coil a current with a triangular profile waveform that is synchronized with the triangular profile waveform of the current in the upper dipole-inducing electromagnetic coil; and C. applying a spatial gradient magnetic field to the metallic SWNTs and the semiconducting SWNTs in the dilute fluid, including: i. providing an upper gradient electromagnetic coil and a lower gradient magnetic coil; ii. applying to the upper gradient electromagnetic coil a current with a square-wave profile waveform; and iii. applying to the lower gradient electromagnetic coil a current with a square-wave profile waveform that is synchronized with the square-wave profile waveform of the current in the upper gradient electromagnetic coil.