High‐Throughput Production With Improved Functionality and Graphitization of Carbon Fine Fibers Developed from Sodium Chloride‐Polyacrylonitrile Precursors

Abstract

Fine polyacrylonitrile (PAN) fibers were produced through a scalable centrifugal spinning process. Sodium chloride (NaCl) was added to the PAN‐dimethylformamide solution to decrease the surface tension and consequently promote a decrease in fiber diameter while increasing the fiber output. The fiber preparation process involved the centrifugal spinning of the PAN‐based solution; developed fibers were stabilized in air at 240°C followed by carbonization at 800°C under a Nitrogen atmosphere. The addition of sodium chloride to the PAN solution led to a 37% decrease in the carbon fiber diameter. The carbon fibers were analyzed by scanning electron microcopy, transmission electron microscopy (TEM), X‐ray diffraction, X‐ray photoelectron spectroscopy (XPS) and electrochemical experiments. The TEM results revealed improved graphitization with the addition of sodium chloride. The XPS analysis showed increased functionality (e.g. O2) on the surface of carbon fibers obtained from PAN/NaCl precursor fibers. A significant improvement was achieved in the electrochemical performance of carbon fibers made from PAN/NaCl precursor fibers compared to those made from pure PAN precursor fibers. POLYM. ENG. SCI., 58:2047–2054, 2018. © 2018 Society of Plastics Engineers

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