Single‐Crystal Rare‐Earth‐Doped Yttrium Orthosilicate Phosphors

Abstract

This is a study of a group of Czochralski grown rare‐earth‐doped Y2SiO5 single‐crystal cathodoluminescent phosphors. Such dopants as Ce3+, Tb3+, Eu3+, Sm3+, Tm3+, Gd3+, and some of their combinations were investigated. Activation by false(Ce3++Gd3+false) , false(Tb3++Gd3+false) , and by false(Tb3++Eu3+false) produced the most efficient blue, green, and red phosphors, respectively. In comparison with our previous best garnet single‐crystal phosphor system, the Y2SiO5‐normalbased blue, green, and red phosphors are by factors 12.7, 1.23, and 0.7 brighter, respectively. Gd3+:Y2SiO5 was shown to be an efficient single line (313 nm) emitting phosphor of very high spectral brightness in UV.

Concentration effect of cerium in (Y0.9−xGd0.1Cex)2SiO5 blue phosphor

“…The Gd in 10 at.% was necessary to enhance cathodoluminescence intensity in practical uses. The enhanced cathodoluminescence of Ce has been expected by the addition of Gd through energy transfer from Gd 3+ to Ce 3+ [13]. The excess amount of Si(OC2H5)4 in 102.5 at.% was necessary to prevent forming Y2O3 impurity due to the high volatility of Si(OC2H5)4 during the preparation [14].…”

“Unusual Ln3+ substitutional defects”: The local chemical environment of Pr3+ and Nd3+ in nanocrystalline TiO2 by Ln–K edge EXAFS

“…Unambiguous examples of this behaviour are the well-known YVO 4 , YPO 4 and Y 2 SiO 5 luminescent crystals, where the dopant Ln 3+ ions are accommodated in the Y 3+ site [5][6][7]. On the other hand, many cases are reported where the Ln 3+ [8] and Sr x Ba 1Àx Nb 2 O 6 (SBN) [9], which are of great interest for their ability to generate the second harmonic of the light emitted from Ln 3+ ions.…”

Long‐Ultraviolet‐Excited White‐Light Emission in Rare‐Earth‐Activated Yttrium‐Oxyorthosilicate

“…A well-known, long-UV excited blue-emitting phosphor, cerium-activated yttrium silicate, (Y 1Àm Ce m ) 2 SiO 5 , is modified here to exhibit white emission at long-UV wavelength excitation. [8][9][10][11][12] (Y 1Àm Ce m ) 2 SiO 5 is efficiently excited at 358 nm with the main emission occurring around 400 nm, giving a small Stokes shift. 9,11 Extensive research has been carried out by several groups 11,13-15 on (Y 1Àm Ce m ) 2 SiO 5 .…”

“…The focus of this research is on finding phosphors that can be efficiently excited at wavelengths between 360 and 400 nm to produce white light and minimize the conversion losses, thus minimizing the Stokes shift. A well‐known, long‐UV excited blue‐emitting phosphor, cerium‐activated yttrium silicate, (Y 1− m Ce m ) 2 SiO 5 , is modified here to exhibit white emission at long‐UV wavelength excitation 8–12 . (Y 1− m Ce m ) 2 SiO 5 is efficiently excited at 358 nm with the main emission occurring around 400 nm, giving a small Stokes shift 9,11 .…”