Materials science research of boron nitride obtained at high pressure and high temperature

Abstract

Boron nitride (BN) is a III–V compound positioned in the upper row of the Periodic Table, and is used in a diverse range of applications. Hexagonal boron nitride (hBN) is known for practical applications such as heat insulation and heat-resistant materials. On the other hand, cubic boron nitride (cBN), which has a sphalerite crystal structure similar to diamond, can be obtained by converting hBN to a high density phase under high pressure and high temperature. Recent some activities studied on BN polymorphic phase transformation and synthesis of high purity cBN as well as hBN single crystals resulted in some new trends such as super-hard materials, wide-band gap materials with deep ultraviolet emission nature and substrate for 2D materials.