Effect of electrochemical treatment in aqueous ammonium bicarbonate on surface properties of PAN-based carbon fibers

The surface properties of PAN-based carbon fibers are electrochemically treated in aqueous ammonium bicarbonate before and after treatment are characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and Dynamic Contact Angle Analysis (DCAA). The results of characterization indicate that the oxygen and nitrogen contents in carbon fiber surface are significantly increased by electrochemical treatment, and amide groups is introduced onto it, which is related to the electrolyte. The AFM photographs illustrate that the roughness of the fiber surface is also increased. The wettability of the fibers is improved after treatment because the surface energy especially the polar part of it is increased.