Synthesis of SrSiO₃:Tb³⁺, Eu³⁺, Li⁺ red phosphors for WLED and study of their luminescence properties

Abstract

A series of Tb3+, Eu3+, Li+ co-doped SrSiO3 phosphors were prepared by high-temperature solid-phase method. XRD results showed that Tb3+ and Eu3+ successfully entered into the SrSiO3 matrix lattice. A strong energy transfer from Tb3+ to Eu3+ exists in the sample, and the energy transfer efficiency between Tb3+ to Eu3+ is calculated to be 94.7%. The doping of the charge compensator Li+ increased the luminescence intensity of SrSiO3:6%Tb3+, 6%Eu3+, 3%Li+ phosphor at 614 nm by 4.2 times and significantly improved the color purity of this phosphor (Cp=85.9%). By the color coordinate analysis, the phosphor color coordinates are located near (0.615, 0.365), which belongs to the red region. The white LED device with a color temperature of 6479K and a color rendering index of 93.8 was obtained through the LED package test, and its luminous performance was very stable under different current drives.

Investigation on structure and photoluminescence properties of Ho3+ doped Ca3(VO4)2 phosphors for luminescent devices

“…The Ca 3 (VO 4 ) 2 :Ho 3+ phosphor is suggested as an excellent candidate for use as the green-emitting component in white LED (w-LED) applications. The correlated color temperature (CCT) of the inorganic phosphor can be estimated using eqn (6) : 66 CCT = −437 n 3 + 3601 n 2 − 6861 n + 5514.31 where, with x e being equal to 0.3320, and y e being equal to 0.1858. 67 The estimated CCT value for the inorganic phosphors lies in the range (5863–6079) K, which suggests that the phosphor is suitable for a work environment where bright illumination is needed.…”