Synthesis of ultraviolet luminescent turbostratic boron nitride powders via a novel low-temperature, low-cost, and high-yield chemical route

A novel chemical route has been established for the synthesis of ultraviolet luminescent turbostratic boron nitride (t-BN) powders, by the reaction of NH4BF4 with NaNH2 at 320 °C for 10 h, and the yield is as high as 90%. The synthesized brown–yellow samples were characterized by XRD, XPS, FT-IR, SAED, and HRTEM, which matched with t-BN. The electronic and optical properties of the product were investigated by PL and UV absorption. UV spectra revealed that the product has two obvious band gaps (∼5.8 and 4.6 eV) and PL spectra showed that it has an ultraviolet emission at 337 nm (image). SEM image indicated that the particle size of the synthesized t-BN is mainly in the range of 1–10 μm. The renascent BF3 and Na3N intermediates are believed to be responsible for the growth of t-BN under mild conditions.