Single-Phased White-Light Phosphors Ca₉Gd(PO₄)₇:Eu²⁺,Mn²⁺ under Near-Ultraviolet Excitation

Abstract

Single-phased white-light-emitting phosphors Ca 9 Gd(PO 4 ) 7 :Eu 2+ ,Mn 2+ were synthesized by solid state reactions. Tuning the Eu 2+ /Mn 2+ ratio via the energy transfer varied the emission hue of Ca 9 Gd(PO 4 ) 7 :0.007Eu 2+ ,xMn 2+ from blue-greenish (0.219, 0.371) to white-light (0.326, 0.328) and eventually to red (0.625, 0.307). The mechanism of transferring energy from a sensitizer Eu 2+ to an activator Mn 2+ in Ca 9 Gd(PO 4 ) 7 :Eu 2+ ,Mn 2+ phosphors was demonstrated to be an electric dipole-quadrupole interaction. Combining a near-UV 380 nm chip and a white-emitting Ca 9 Gd(PO 4 ) 7 :0.007Eu 2+ ,0.02Mn 2+ phosphor produced a white-light near-UV LED, demonstrating CIE chromaticity coordinates of (0.312, 0.327) and a color temperature of 6569 K.

Synthesis and luminescent properties of Eu3+/Eu2+ co-doped calcium aluminosilicate glass–ceramics

“…White light emitting diodes (W-LEDs) have attracted significant attention owing to their superior efficiency and longer lifetime for display and lighting [1][2][3][4][5][6]. One of the methods for making W-LEDs is the combination of UV or blue LED chips with actually one, two or three phosphor materials.…”

Eu3+ ions co-doped CLPO: Dy3+ single phase white-light emitting phosphors for near UV-based white LEDs

“…Nowadays, synthesis of rare-earth ions activated phosphors for white-light emitting applications is of growing interest, especially for ultraviolet (UV)/near UV (NUV) excitation based white light-emitting diodes (WLEDs) [1][2][3]. These WLEDs which are beneficial as indoor/outdoor illumination sources save up to 70% of energy in an environmentally-friendly way when compared to conventional light sources.…”

Effects of co-doped Li+ ions on luminescence of CaWO4:Sm3+ nanoparticles

“…The WLED can be obtained by the combination of a blue LED chip and YAG:Ce 3? yellow-emitting phosphor [6], the combination of a near-ultraviolet LED chip coating with three different phases, red, green, and blue-emitting phosphors [7], and single-phase white-emitting phosphors [8]. With development of ultraviolet LEDdriven inorganic phosphors, the use of the combination of a near-ultraviolet LED chip coating with red, green, and blue-emitting phosphors for general illumination is proposed to become price-competitive with current luminescence lamps by the year 2020.…”