Direct annealing of electrospun synthesized high-performance porous SnO2 hollow nanofibers for gas sensors

Abstract

Hollow stannic oxide (SnO₂) nanofibers were fabricated by direct annealing of electrospun precursor nanofibers. In this approach, different SnO₂ nanostructures were synthesized by electrospinning a PVP/salt solution, and then calcining at a high temperature with an appropriate heating rate. The nanofibers were identified as hollow in structure, with diameters ranging from 80 to 100 nm and a wall thickness up to about 20 nm. The gas sensor based on hollow SnO₂ nanofibers exhibits a high response and a quick response-recovery to carbon tetrachloride, which is much better than that of solid SnO₂ nanofibers. It is believed that its high gas sensing performance is derived from the large surface area, and high porosity, which lead to highly effective surface interactions between the target gas molecules and the surface active sites.