Accelerated Graphitization of PAN-Based Carbon Fibers: K<sup>+</sup>-Effected Graphitization via Laser Irradiation
Zhenghe Zhang, Lijian Song, Lisheng Cheng, Jing Tan, Weimin Yang
Abstract
Graphitization progress of polyacrylonitrile (PAN)-based carbon fibers is closely dependent on the treatment temperature; exactly, controlling the microstructural morphology of carbon layers in the fibrous solid state can accelerate the formation of a highly graphitic structure. The present work exhibited the accelerated graphitization of PAN-based carbon fibers by the effect of K+ on microstructure evolution under laser irradiation. Chemical and microstructure characterization reveals that a much higher degree of graphitization is achieved via the K+ effect after the laser irradiation than by pure laser treatment at the same low temperature of about 2000 °C. Ordered and large-sized graphite-like microcrystals can be formed as well. The reactive molecular simulation further provided insights into the acceleration mechanism of the K+ effect during the graphitization progress. Thus, based on these results, K+-effected graphitization via laser irradiation can be a promising alternative for the efficient and eco-friendly mass production of graphite fibers.