Orthovanadate Phosphors with Zircon Structure

Abstract

not Available.

Luminescence of Eu3+ Activated Thorium, Alkali Metal Vanadates

“…Samples were checked by x-ray analysis. The measurement of the optical properties was performed as indicated previously (6).…”

“…In all the complex vanadates we have examined there is a steady fall in brightness as the temperature is raised. An exception is CaTh(VO4), a compound reported by Avella (6), which peaks at about 160~ However, the over-all brightness of this vanadate is rather poor. In contrast the thorium vanadates with lithium and sodium are much brighter than YVO4:Eu at room temperature so that, although they fall in brightness with increasing temperature, they are about equal in brightness to YVO4:Eu at 200~ This is within the range of the bulb wall operating temperature of low wattage high-pressure mercury vapor lamps, so these phosphors could possibly find application for color correction in this type of lamp.…”

“…Other vanadates with this structure are therefore of interest in view of the current commercial applications of this phosphor in the television (3) and lighting industries (4). Such materials have been synthesized by Schwarz (5), and Avella has recently described the Eu 3+ emission from compounds of the type M TM M II (VO4)2:Eu where M II and M Iv are, respectively, divalent and tetravalent metals (6). We report here briefly on other vanadates with the zircon structure having the general formula M2 Iv M ~ (VO4)3, where M Iv is thorium and M I is a univalent alkali metal.…”