A facile sulfur vapor assisted reaction method to grow boron nitride nanorings at relative low temperature

Boron nitride (BN) nanorings were synthesized using a sulfur vapor assisted solid-state method at 600 degrees C. The rings had typical diameters of 100-300 nm, and the shells were 5-20 nm thick and about 50 nm wide. On the basis of the characterization of X-ray powder diffraction pattern (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transformation infrared spectroscopy (FTIR) measurement, the as-prepared product was pure-phase hexagonal BN. High-resolution transmission electron microscopy (HRTEM) images proved that the nanorings were formed through the coiling of the (002) planes of hexagonal BN. A possible growth process for BN nanorings is suggested.