Colloidal ordering under external electric fields

• Main Author: Li, Ning, 1982-
• Other Authors: Memorial University of Newfoundland. Dept. of Physics and Physical Oceanography
• Format: Text
• Language: English
• Published: 2008
• Subjects: Colloids > Electric properties; Electrokinetics; Newfoundland studies; University of Newfoundland
• Online Access: http://collections.mun.ca/cdm/ref/collection/theses4/id/110204

Thesis (M.Sc.)--Memorial University of Newfoundland, 2008. Physics and Physical Oceanography Includes bibliographical references (leaves 149-154) Colloidal science is an important branch of "soft condensed matter", which incorporates insights from chemistry, physics and biology. In this thesis, I will present the synthesis of fluorescently labeled core-shell silica colloids, and the laser scanning confocal microscopy studies of these colloidal silica particles under an external linear or rotating high-frequency alternating electric field. The external AC field controls the averaged dipolar interaction between the silica microspheres. We investigated bond order parameters upon increasing the field and found the threshold of the field to form dual-particle bonds and the average bond direction dependence on the field. We also studied the pair correlation function of these silica colloids in external electric fields. Moreover, we studied the equilibrium sedimentation profiles of these colloidal suspensions and found the dependence of isothermal osmotic compressibility on the applied electric field energy.