Synthesis of iron oxide nanoneedles and their field emission properties

In this paper, the fabrication of iron oxide (α-Fe2O3) nanoneedle arrays has been achieved. By thermally oxidizing iron plates at 650 deg. C under vacuum, nanoneedles with 2-5 μm in length are obtained with high yield. The diameters of the nanoneedle tips are typically as small as several nanometers. The field emission measurement shows that these nanoneedles have strong electron field emission abilities, with relatively low turn-on fields of 4.8 Vμm-1. This makes the Fe2O3 nanoneedle arrays one of the promising candidates as the field emitters.