Amazing ageing property and in situ comparative study of field emission from tungsten oxide nanowires

摘要

In this work, needle-shaping of tungsten oxide nanowires occurred during field emission characterization. Compared with nanowires with a flat apex, needle-shaped emitters showed a lower threshold field of 11.9 V μm -1 for 1 mA cm-2 and a higher emission current of 1120 μA at 16.2 V μm-1. Most notably, the measured ageing current dramatically increased by more than four times until it slightly decreased, tending towards stability. In addition, the samples showed striking difference in their nonlinear Fowler-Nordheim plot before and after ageing tests. Selected area diffraction and transmission electron microscope characterizations were used to further study these amazing results.