Boride

The borides are a very large group of compounds that are generally high melting and are covalent more than ionic in nature.

[2] LaB6 is an inert refractory compound, used in hot cathodes because of its low work function which gives it a high rate of thermionic emission of electrons; YB66 crystals, grown by an indirect-heating floating zone method, are used as monochromators for low-energy synchrotron X-rays.

[3] VB2 has shown some promise as potential material with higher energy capacity than lithium for batteries.

Some are easily formed and this explains their use in making turbine blades, rocket nozzles, etc.

Recent investigations into this class of borides have revealed a wealth of interesting properties such as super conductivity at 39 K in MgB2 and the ultra-incompressibility of OsB2 and ReB2.