Large scale synthesis of nanoporous BN flake with high surface areas

•Nanoporous BN flake was synthesized at 550 °C in autoclaves without any template.•The as-prepared BN nanoporous flake exhibits a high surface area of 214 m2 g−1.•The BN flake has good thermal stability and oxidation resistance up to 800 °C.

Nanoporous boron nitride (BN) flake was synthesized in large scale at temperatures between 550 and 600 °C for 10 h via the simple reaction between NaBH4 and CH5N3S. X-ray diffraction and Fourier transform infrared spectra confirm the formation of hexagonal BN. Examination by high-resolution transmission electron microscope reveals that the product is comprised of nanoporous flake, which exhibits a high surface area of 214 m2 g−1 characterized by nitrogen adsorption–desorption isotherms. The nanoporous BN flake has good thermal stability and oxidation resistance up to 800 °C measured by thermogravimetric analysis.