Hydrolyzed colloid reaction (HCR) technique for phosphor powder preparation

Undoped and Eu3+, Ce3+ and Tb3+-doped YVO4 YPO4, LaPO4 and YVxP1-xO4 were prepared in H2O by the recently introduced hydrolyzed colloid reaction (HCR) technique working at low temperature (< 100 degrees C) and atmospheric pressure. Two intermediate - partially hydrophobic - complex colloidal mixtures with metastable characteristics can transform into the stable orthovanadate-orthophosphate phase due to intensive hydrolysis. in contrast with the other low temperature reacting processes - like the sol-gel technique. which makes an amorphous structure - the HCR method can produce crystalline structures in nanometer size ranges. The reaction, morphology, incorporation of activators and different luminescent characteristics are surveyed in this letter-type paper selected from our previous results. (C) 1999 Published by Elsevier Science B.V. All rights reserved.