Abstract
We describe the growth of gallium nitride nanoneedles synthesized via a self-catalytic process. Transmission electron microscopy studies confirmed the gallium nitride nanoneedles to be single-crystalline with a predominant (10-10) growth direction. The nanoneedles are facetted and no catalyst particles are observed at their tips. We propose that the nanowires formed from nanosized gallium droplets supersaturated with nitrogen, but under Ga-rich conditions, the nanowires tapered to form nanoneedles. Excess Ga in the metallic droplets then reacted to form gallium nitride microcrystals.