Synthesis and field emission of two kinds of hierarchical SnO2 nanostructures

Novel self-organized hierarchical SnO2 nanostructures have been successfully prepared by vapor phase transport with the assistance of a stainless steel grid at 950 ∘C. Scanning electron microscopy shows that the two kinds of products synthesized display interesting sallow-like and fishbone-like morphologies, in which numerous secondary branches are grown randomly around the main stems. Transmission electron microscopy analysis indicates that SnO2 nanowires are single crystals. Field emission measurements of these nanostructures showed a high emission current density and low turn-on field of 1.88 and 2.36 V μm−1, which is comparable to that of one-dimensional SnO2 nanostructure. We also studied the influence of gas adsorption on the field emission properties of hierarchical SnO2 nanostructures. The good performance for field emission makes the hierarchical SnO2 nanostructures promising candidates for further applications in field emission microelectronic devices.