Near-ultraviolet excitable orange-yellow Sr3(Al2O5)Cl2:Eu2+ phosphor for potential application in light-emitting diodes

Abstract

Sr 3 ( Al 2 O 5 ) Cl 2 phosphor doped with Eu2+ was prepared by a soli-state reaction. This phosphor emits a broad orange-yellow luminescence with a peak wavelength of 620nm and a full width at half maximum of about 175nm under near-ultraviolet (NUV) excitation at ∼400nm. Yellow light-emitting diodes (LEDs) for general lighting were fabricated by combining Sr3(Al2O5)Cl2:Eu2+ phosphor with an NUV chip. The phosphor-converted LEDs had a color temperature of about 2300K and their color rendering index was 74.

A new yellowish-green-emitting phosphor: Eu2+-doped K4CaSi3O9

“…Many studies on Eu 2+ -activated silicates have been published [12][13][14], e.g., SrSiO 3 :Eu 2+ [15], Sr 2 SiO 4 :Eu 2+ [16], M 3 SiO 5 :Eu 2+ (M = Sr, Ba) [17], MSi 2 O 5 :Eu 2+ (M = Ca, Sr, Ba) [18], SrCaSiO 4 Gunawardane and Glasser [27] first reported the basic crystallographic data of unit cell parameters of K 4 CaSi 3 O 9 . Recently, Arroyabe et al [28] have investigated the detailed crystal structure of K 4 CaSi 3 O 9 by X-ray diffraction techniques and Raman spectroscopy.…”

Efficient and tuneable photoluminescent boehmite hybrid nanoplates lacking metal activator centres for single-phase white LEDs

“…In ultraviolet-pumped WLEDs, multilayers of phosphors with distinct colour emission are generally used [14][15][16][17][18][19] . However, due to the reabsorption of light within the multicomponent phosphors, non-uniformity of luminescent properties with colour altering and a decrease of luminous efficiency are generally observed 2,20 .…”

Spectral and thermal properties of Dy3+-doped NaGdTiO4 phosphors

“…As can be seen from Fig. 8 In general, luminescence intensity decreases with an increase of temperature [28,29]. It is known that the luminescent ion can reach the ground state via several pathways, such as cascade multiphonon relaxation, energy transfer from the luminescent level and crossover effect, etc.…”

“…After excluding the above two possible mechanisms of fluorescence temperature quenching, the crossover process should be checked to find the physical nature of temperature dependent fluorescence quenching of Dy 3+ . Besides, it has been widely observed and extensively studied in Eu 3+ -doped luminescent materials [29,[32][33][34]. In fact, the crossover quenching is a thermal activation process in which the relationship between luminescence intensity and sample temperature can be described as the following equation [35]:…”