Synthesis of Ga2O3 Nanorods with Ultra-Sharp Tips for High-Performance Field Emission Devices

We synthesized catalyst-free beta-Ga2O3 nanorods with terminated ultra-sharp tips by heat treating single crystalline GaAs in a chemical vapor deposition (CVD) chamber without introducing a precursor. The unique, straight-forward, synthetic route and a possible growth mechanism are discussed to explain the different morphology of the grown nanorods and the ultra-sharp nanostructures. The morphology and structure of the nanorods were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and Raman-spectroscopy. The ultra-sharp tips were found to have radii of similar to 3-5 nnn and were utilized to achieve enhanced field emission. The field emission characteristics demonstrated a turn-on field of 2.1 V mu m(-1), a threshold electric field of 5.6 V mu m(-1), and a geometrical field enhancement factor of 3786, making them comparable to nanostructured diamond and highly oriented single wall carbon nanotubes.