Field emission from diamond-coated multiwalled carbon nanotube “teepee” structures

Dense arrays of vertically aligned multiwalled carbon nanotubes (MWCNTs) have been seeded with a nanodiamond suspension in methanol using electrospray deposition. This treatment caused the tips of groups of 20–40 MWCNTs to stick together forming structures resembling “teepees.” Subsequent short chemical vapour deposition experiments using standard diamond-growing conditions allowed the nanodiamond seeds to grow into a thin continuous film, locking the teepee structures into this shape. Field emission tests show that these diamond-coated carbon nanotubes (CNTs) teepees retain the low threshold voltage of the uncoated CNTs but with greatly improved emission stability and lifetime.