Electrokinetics of Carbon Fibers Produced by a Direct Oxyfluorination

PAN-based carbon fibers were treated by a direct oxyfluorination method to study the chemical surface composition and electrokinetic behavior of the fibers. The physicochemical properties of the fibers were investigated by using a photoelectron spectroscopy (XPS) and zeta (ζ)-potential. As a result, the surface functional groups, including C-O, C=O, HO-C=O, and C-F_x after oxyfluorination, were formed on the carbon fiber surfaces. And the time dependence of the ζ-potential of oxyfluorinated carbon fibers reflected the surface bonding state of the obtained fiber materials, due to the dissociation of C-F_x groups. These results could be explained by the modification of chemical composition and the formation of physical bonding on the fiber surfaces, which could be attributed to the oxyfluorination.