Iodine-aided fabrication of hollow carbon fibers from solid poly(vinyl alcohol) fibers

Hollow carbon fibers were fabricated from solid poly(vinyl alcohol) (PVA) fibers with the aid of an iodine pretreatment followed by stabilization. Iodination converted the chemical structure of PVA to polyene form due to dehydration reaction, and stabilization of heat treatment at 200 °C in air provided insolubilization of iodinated PVA fibers. These processes extremely enhanced the carbon yield and enabled to obtain intact carbon fiber. By selective iodination and subsequent stabilization within the fiber cross-section close to the fiber surface, hollow carbon fibers were made through the carbonization.