Low temperature benzene thermal synthesis and characterization of boron nitride nanocrystals

Hexagonal boron nitride nanocrystals were synthesized by reacting Li3N and BBr3 at low temperature benzene thermal conditions and they are characteriz ed by XRD, IR, TEM and XPS. The results show that when the temperature is l ow, hexagonal BN nanocrystals can be obtained which are uniform in granular ity and regular shape. However, benzene molecules dissociated on the surfac e of BN nanocrystals at higher temperature, and that it is difficult to obt ain BN samples with higher purity. In addition, thermal analysis of hexagon al BN nanocrystals shows that when the average size reduced to about 1.0 nm , its melting point decreases from 2967 degreesC of the bulk BN to about 12 40 degreesC. (C) 2001 Elsevier Science B.V. All rights reserved.