Thermally induced formation of 2D hexagonal BN nanoplates with tunable characteristics

•Thermally induced combustion route was developed for synthesizing BN nanoplates from B2O3.•Mg was used as reductive agent and NH4Cl as an effective nitrogen source.•Temperature–time profiles and the combustion parameters were recorded and discussed.•BN with an average edge length from 50 nm to several micrometer and thickness from 5 to 100 nm were prepared.•Our study clarifies the formation mechanism of BN in the combustion wave.

We have investigated a thermally induced combustion route for preparing 2D hexagonal BN nanoplates from B2O3+(3+0.5k)Mg+kNH4Cl solid system, for k=1–4 interval. Temperature–time profiles recorded by thermocouples indicated the existence of two sequential exothermic processes in the combustion wave leading to the BN nanoplates formation. The resulting BN nanoplates were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy, PL spectrometry, and Brunauer–Emmett–Teller surface area analysis. It was found that B2O3 was converted into BN completely (by XRD) at 1450–1930 °C within tens of seconds in a single-step synthesis process. The BN prepared at a k=1–4 interval comprised well-shaped nanoplates with an average edge length ranging from 50 nm to several micrometer and thickness from 5 to 100 nm. The specific surface area of BN nanoplates was 13.7 g/m2 for k=2 and 28.4 m2/g for k=4.

Graphical abstract2D hexagonal BN nanoplates with an average edge length ranging from 50 nm to several micrometer and thickness from 5 to 100 nm were prepared by combustion of B2O3+(3+0.5k)Mg+kNH4Cl solid mixture in nitrogen atmosphere.Figure optionsDownload full-size imageDownload as PowerPoint slide