Electron emission originated from free-electron-like states of alkali-doped boron-nitride nanotubes

The electronic structures and electron emission properties of alkali-doped boron-nitride nanotubes (BNNTs) are examined by using density-functional theory calculations. The studies have shown that the alkali-doped BNNT is an excellent electron emitter in terms of the large emission current as well as its chemical and mechanical stability.