Low-temperature synthesis of amorphous carbon nanoneedle and study on its field emission property

Amorphous carbon needle-like structure has been synthesized at temperature as low as 250 °C via reaction of ammonium chloride with ferrocene. The microstructure of the as-prepared carbon powder has been investigated with the help of a scanning electron microscope and a transmission electron microscope. The X-ray diffraction pattern as well as selected area electron diffraction pattern confirmed the amorphous nature of the samples. The prepared carbon needles show a good field emission property with turn-on field as low as 3.85 V/μm. The method developed here has the simplicity both in terms of process control and the equipmental set up, so that it may provide a possibility for large-scale production and may find applications in field emission display.