Abstract
Hexagonal-boron nitride (
h
-BN) fullerenes were synthesized from a graphene oxide (GO) template by simultaneously heating the GO and B
2
O
3
in the presence of NH
3
gas. Transmission electron microscopy (TEM) observations revealed that a considerable amount of product had a fullerene-like nanostructure. Typical BN fullerenes have a polyhedral shape, being hollow nanocages. Lattice-resolved TEM and X-ray diffraction consistently demonstrated the formation of
h
-BN fullerenes. The FTIR spectrum exhibited absorption bands at approximately 800 and 1378 cm
-1
, which were related to the
h
-BN structure. The Raman spectra exhibited peaks at 1368 and 1399 cm
-1
, which can be related to BN sheets and BN fullerenes, respectively. The photoluminescence spectrum of the
h
-BN fullerenes taken at 8 K exhibited intense white-light emission. To reveal the origin of the broad emission band, which could be a superimposition of several peaks, we used a deconvolution procedure based on Gaussian functions. We proposed a growth mechanism of the
h
-BN fullerenes and verified it with a thermodynamic calculation. This work provides a cost-effective approach to synthesize fullerene-type boron nitride on a production scale.