Temperature-Dependent Morphology Evolution of Boron Nitride and Boron Carbonitride Nanostructures

Boron nitride (BN) and boron carbonitride (BCN) nanostructures with versatile morphology were synthesized at different temperatures. The morphologies such as smooth microspheres, nanoflake-decorated microspheres, solid nanowires, hollow nanotubes (bamboo-like nanotubes, quasi-cylindrical nanotubes, and cylindrical nanotubes), and nanosheet-assembled microwires have been observed. Systematic investigation showed that the reaction temperature was responsible for the versatile morphologies through influencing the guiding effect of catalyst alloy droplet and the diffusion rates of growth species. The diffusion rate differences between surface diffusion (along the surface of the droplet) and bulk diffusion (through the bulk of the droplet) at different reaction temperatures were suggested to affect the final structure of the BN and BCN nanostructures.