Lithium-sensitised, cerium-activated yttrium:orthophosphate-phosphor - obtd. by mixing co-ppte. of yttrium- and cerium- oxide, borophosphate and lithium carbonate, burning in reducing atmos., washing, etc.

摘要

Cerium-activated yttrium orthophosphate-phosphor of formula Y1-x-t(1/3)yCexLiyPO4 is new, where x = 0.01 to 0.1 and y = 0.0001 to 0.5 (0.001). Prodn. of the Lithium Sensitised cerium-activated yttrium orthophosphate-phosphor comprises mixing a co-ppte. of yttrium- and cerium oxide, borophosphate and lithium carbonate followed by burning at approximately 1200 deg.C in a reducing atmos. The burnt mixt. is washed in dil. acid and finally washed and dried. ADVANTAGE - The Li-sensitised YPO4:Ce has increased emission efficiency and is non-toxic compared to p.a. Th-sensitised phosphors