Electrospun polystyrene fiber-templating ultrafine gold hollow fiber production

Ultrafine gold hollow fibers of about 1.5 μm in outer diameter and 1 μm in hollow core diameter, i.e., about 250 nm of gold sheath thickness, were produced in combination with electrospinning technique, photoreduction, electroless plating, and heat treatment for removing template polymer fibers. The gold sheath was fabricated through electroless plating on electrospun polystyrene fibers of about 1 μm diameter using the gold nanoparticles formed in situ in the fibers by irradiation of ultraviolet light as seeds of the gold sheath formation. Then, a hollow core structure was developed by treating the resultant fibers at 180, 350, or 800 °C. Scanning electron microscopy imaging showed the formation of a hollow core structure in the fibers by the treatment at 180 °C as well as those treated at 350 and 500 °C. These results demonstrate the possibility of fabrication of ultrafine gold hollow fibers using electrospun polystyrene fibers as a template of the hollow core structure.