A New Approach to Synthesis of Ultrathin Hexagonal Boron Nitride Nanoparticles by Two-Stage Thermal Treatment
Abstract
A method for fabricating hexagonal boron nitride (h-BN) nanoparticles 2–10 nm in size with a crystallinity of up to 99% has been developed. The method is based on a two-stage heat treatment at temperatures of 600 and 1000°C, using boric acid, urea, nitrogen, and hydrogen. The h-BN hexagonal structure with an interplanar spacing of 3.3 Å, narrow size distribution, and uniform distribution of elements in the material have been confirmed by X-ray phase analysis, transmission electron microscopy, selected-area electron diffraction, and analysis of electron density maps. The proposed approach excludes the use of toxic ammonia and is energy efficient and suitable for industrial scaling. The obtained nanoparticles can be used in tribological coatings and lubricants.