Chemistry Reference
In-Depth Information
the reaction mixture, allowing a control on the number of BN layers
(Fig. 18). We believe that this is the first report of a bottom-up chemical
synthesis of few-layer BN, enabling large-scale production. The surface
area of the BN layers increases with the decrease in layer thickness as
expected, the sample with lowest layer thickness exhibiting a surface
area of 927 m
2
/g and high CO
2
uptake. Few-layer BN can be
functionalized and solubilized by employing Lewis bases. First-
principles simulations show that it is energetically easy for few-layer BN
to form stacking faults that involve slips and twists of adjacent planes
resulting in inhomogeneity in the interplanar distances and deform
through forming ripples. It has a smaller buckling strength and elastic
stiffness than graphene. Long-range Coulomb interactions are found to
be important to the stability of the different structures of BN. Our
calculations demonstrate only weak interaction of hydrogen with BN
sheets. Graphene analogues of BN may find several interesting
applications. They can be used to form composites with polymers, with
desirable applications.
Fig. 18. TEM images of few-layer BN prepared with (a) 1:12, (b) 1:24, and (c) 1:48 boric
acid/urea mixture (From reference 82).
