Hexagonal boron nitride (hBN) is a synthetic, two-dimensional material that is isoelectric to graphene but composed of alternating nitrogen and boron atoms rather than carbon atoms. It was first prepared in the 1840s by WH Balmain through a reaction incorporating molten boric acid and potassium cyanide. However, it was not until the 1950s that the synthesis of hBN was made more practical to address industrial needs. Current practical synthesis methods include Nag's boric acid-urea1 and chemical vapor deposition. Other types of boron nitride (BN) include cuboidal BN, rhombohedral BN, and wurtzite BN. Cubic BN is thermally stable up to 1000 C, with a phase transition from cBN to hBN reported between 1000 and 1800 C. hBN is thermally conductive and electrically insulating with a low density (2.27g/cm3) and high thermal stability . Like graphite, hBN consists of layers of individual sheets stacked to form flakes or particles. As a binary-based material, hBN exhibits properties such as a large band gap (5.9eV), high oxidative resistance, and inertness towards most chemicals. The differences in the polarity of B and N hinder the delocalization of the pi electrons, thus preventing conjugation. This is unlike graphene, whose lack of a band gap results from fully delocalized pi electrons. Despite the lack of conjugation, the basal plane of hBN sheets is hydrophobic as the nitrogen and boron atoms are less polar due to sp 2 hybridization. However, like graphite, the hBN stacked sheets must be exfoliated and dispersed for many of the extraordinary properties to be utilized in nanocomposites.