▎ 摘　　要

Nickel nanoparticles (NiNPs) prepared in tetraglyme (TG) efficiently catalyzed the conversion of ammonia borane (AB, NH3BH3) to borazine (B3N3H6). Under the optimized conditions, 3 mol% of the NiNPs were introduced into a 1.5 M AB solution in TG and held at 80 degrees C for 6 h under a dynamic vacuum that was maintained at 30 torr. Borazine was isolated through a series of -45 degrees C, -78 degrees C, and -196 degrees C traps to give (-78 degrees C trap) pure borazine in 53% yield. The borazine produced was then utilized as a molecular precursor for high quality h-BN (white graphene) and large area h-BN sheets were prepared by applying low pressure chemical vapor deposition (LPCVD). Ultra-thin (single to few layers) h-BN was synthesized on Ni foil at the optimal ratio between borazine and NH3, and the number of layers was tuned by varying the NH3 partial pressure.