Structure and field-emission properties of W/WO2.72 heterostructures fabricated by vapor deposition

One dimensional W/WO2.72 heterostructures were successfully synthesized using WO3 as the raw material by a simple two-step chemical vapor deposition process. The morphology and microstructure of the W/WO2.72 heterostuctures were characterized using scanning electron microscopy and transmission electron microscopy. The results indicate that the long and straight central axial W whiskers grow along [1 1 0] direction, while the branched WO2.72 nanowires grow on the side surface of the W whiskers along the radial direction, with [0 1 0] as the growth direction. The as-synthesized heterostuctures exhibit enhanced field emission property over the single W whiskers, and could be used as a candidate for field-emission devices and ultrahigh sensitivity sensors due to their unique composition and structure.