Electric-Field-Induced Dispersion of Multiwalled Carbon Nanotubes in Nematic Liquid Crystal

Effect of electric field and frequency on multiwalled carbon nanotubes (MWCNTs) dispersion in liquid crystal (LC) medium has been investigated. At zero field, large MWCNT aggregates are found due to insufficient dispersion throughout the cell under optical microscopy. As the vertical field strength increases gradually, the cluster sizes become smaller, and at above critical field strength, the clusters disappear and are dispersed finally into LC medium. The dispersion of CNT clusters remained stable even after the field is removed. Strong correlation of cluster sizes with field strength was also observed. The dispersion of clusters at above critical field was also confirmed by the light absorption. This robustness of field-induced dispersion of CNTs provides a new method of improving solubility of CNTs in LC medium, which can be advantageous in numerous CNT-LC optoelectronic devices.