Stabilizing the metastable superhard material wurtzite boron nitride by three-dimensional networks of planar defects

Research Highlight

Superhard material promises next-generation electronics

© Cavan Images/Getty

© Cavan Images/Getty

Millimetre-sized crystals of the superhard semiconductor wurtzite boron nitride (w-BN) can now be fabricated at atmospheric pressure and moderate temperatures.

As hard as a diamond and having a wide electronic band gap and high thermal conductivity, w-BN is a metastable form of BN that is attracting considerable attention for potential use in next-generation electronics.

Current methods for producing w-BN involve direct conversion of hexagonal BN (h-BN) at high pressures. However, the bulk of the material returns to its h-BN form when the pressure is released, leaving only small amounts of w-BN crystals with micrometre-sized grains.

By introducing planar defects into the crystals, a team of scientists led by researchers from the Advanced Institute for Materials Research at Tohoku University was able to delay the transformation from w-BN to h-BN and produce millimetre-sized crystals of w-BN.

Supported content

  1. PNAS 116, 11181–11186 (2019). doi: 10.1073/pnas.1902820116
Institutions Share
Shenyang National Laboratory for Materials Science (SYNL), IMR CAS, China 0.31
Research Center for Functional Materials (RCFM), NIMS, Japan 0.25
WPI Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Japan 0.17
Nanostructures Research Laboratory, JFCC, Japan 0.17
College of Aerospace Engineering, CQU, China 0.06
Institute of Engineering Innovation (IEI), UTokyo, Japan 0.04