SnO₂ nanofibers prepared by wet spinning using an ordered porous alumina spinneret

SnO₂ nanofibers with uniform diameters were obtained by wet spinning using ordered anodic porous alumina as a spinneret, followed by heat treatment. Ordered alumina through-hole membrane is a suitable spinneret material for nanofiber spinning owing to its nanohole array structure with uniform-sizes holes. A polymer solution containing a Sn salt was used as a precursor solution for the wet spinning. Polymer nanofibers containing the Sn salt were continuously formed as the precursor passed through the alumina holes into a coagulating solution. Monodisperse nanofiber structures were successfully maintained, even after heat treatment at 600 °C. This process enabled the preparation of monodisperse SnO₂ nanofibers with diameters below 100 nm, as well as the precise control of fiber diameter by changing the hole size of the porous alumina spinneret. The obtained SnO₂ nanofibers will be useful in various functional devices.