Catalytic graphitization of Mo-B-doped polyacrylonitrile (PAN)-based carbon fibers

Abstract

A novel carbon fiber pretreatment was proposed. Polyacrylonitrile (PAN)-based carbon fibers were first anodized in H₃PO₄ electrolyte to achieve an active surface, and then coated with Mo-B catalysts by immersed the carbon fibers in a uniformly dispersed Mo-B sol. The as-treated carbon fibers were then graphitized at 2 400 °C for 2 h. The structural changes were characterized by X-ray diffractometry (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electronic microscopy (HRTEM). The results show that much better graphitization can be achieved in the presence of Mo-B, with an interlayer spacing (d₀₀₂) of 0.335 8 nm and a crystalline size (L_c) of 28 nm.

Keywords

polyacrylonitrile (PAN)-based carbon fibers / anodization / sol / catalytic graphitization / Mo / B

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