A Novel BN Polymorph in P4/mbm Phase with a (4,4) Nanotube

Abstract

Herein, based on density functional theory, a new boron nitride structure derived from diamond is designed, and its stability is also proved. The new boron nitride structure is denoted as P4/mbm BN. The elastic moduli (bulk modulus, shear modulus, and Young's modulus) of P4/mbm BN are slightly greater than those of C72 and T carbon, and the shear modulus and Young's modulus are larger than those of P‐4m2 B7N7, B11N11, and B15N15. The shear modulus and Young's modulus of P4/mbm BN exhibit a smaller mechanical anisotropy than that of P‐4m2 B7N7, B11N11, and B15N15, where P‐4m2 B15N15 exhibits the greatest mechanical anisotropy of shear modulus and Young's modulus. The anisotropy of shear modulus in the (100), (010) plane of P‐4m2 B15N15 is 26.5 times that of P4/mbm BN, and the mechanical anisotropy of Young's modulus in (110) plane of P‐4m2 B15N15 is 35.6 times that of P4/mbm BN. P4/mbm BN is a wide and indirect bandgap semiconductor material with bandgap of 4.8 eV. Compared with silicon carbide and gallium nitride, P4/mbm BN has a wider bandgap, it might be more suitable for making high temperature, high frequency, radiation resistance, and high‐power devices.