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.

2D 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 as PowerPoint slide