Synthesis and field-emission of aligned SnO2 nanotubes arrays

Aligned tin dioxide (SnO2) nanotubes have been synthesized by high-frequency inductive heating. Nanotubes with high yield were grown on silicon substrates in less than 5 min, using SnO2 and graphite as the source powder. Scanning electron microscopy and transmission electron microscopy showed nanotube with diameters from 50 to 100 nm and lengths up to tens of mircrometers. The SnO2 nanotubes synthesized under the optimum condition have better field-emission characteristics. The turn-on field needed to produce a current density of 10 μA/cm2 is found to be 1.64 V/μm. The samples show good field-emission properties with a fairly stable emission current. This type of SnO2 nanotubes can be applied as field emitters in displays as well as vacuum electric devices.