简介 |
Oxidic nanocrystal production, by organometallic complex or volatile inorganic compound vapor decomposition in a low pressure hot reactor zone (18) in the presence of reactive gas, is new. An oxidic nanocrystal production process comprises (a) evaporating organometallic complexes or volatile inorganic compounds of host lattice ions in a vaporizer (12); (b) transporting the resulting gas phase by a carrier gas into a hot zone (18) of a reactor (16) supplied with reactive gas; and (c) decomposing the complexes or compounds in the hot zone at 1-1000 mbar to form oxidic nanocrystals which are deposited in an adsorption trap (20). Independent claims are also included for the following : (i) apparatus for carrying out the above process; and (ii) a phosphor comprising a rare earth metal-activated host lattice of especially Y, Gd, Mg, Mg, Ca, Ba and/or Al oxide or oxysulfide nanocrystals and exhibiting little agglomeration, a mean particle size of 1-20 nm and a cubic crystalline structure. Preferred Features : The hot zone (18) is also supplied with evaporated organometallic complexes or volatile inorganic compounds of dopant ions. |