Tunable emission in Dy3+/Eu3+-doped BaLu2Si3O10 trisilicate structure for white light-emitting diode applications

Abstract

The development of phosphors with high quantum efficiency and excellent thermal stability remains a challenging task for phosphor-converted white light-emitting diodes (w-LEDs). In this work, trisilicate-structured BaLu2Si3O10: Dy3+/Eu3+ (BLSO: Dy3+/Eu3+) series phosphors with stable performance were synthesized by high-temperature solid-phase reaction method. The results show that the Dy3+ monodoped trisilicate phosphor lacks a red component and exhibits cool white light properties, so Eu3+ ions are introduced into the matrix to compensate for the lack of the orange-red emission region. A detailed investigation of the photoluminescence properties of the double-doped phosphor light shows that Eu3+ ions can be well sensitized by Dy3+ under near-UV excitation at 350 nm. According to the Dexter’s energy transfer equation and the Inokuti-Hirayama model, the energy transfer mechanism from Dy3+ to Eu3+ ions was confirmed as the electric dipole-quadrupole interaction, and the CDA value of the interaction parameter for the sample with Eu3+= 0.1 confirmed was 3.128 × 10−54 cm6 s−1, and the energy transmission efficiency could reach 70.09%. By controlling the wavelength of the excitation light and the Eu3+ ion concentration, the CIE coordinates of BLSO can be color adjusted in the white-yellow-orange-red region. The composition-optimized BLSO: Dy3+, Eu3+ phosphor has a CCT of 5622 K. The luminescence intensity of BLSO: 0.04Dy3+, 0.1Eu3+ at 423 K can be maintained at 81.15% of the luminescence intensity at 303 K, which is a satisfactory shows thermal fluorescence stability. From the obtained results, the prepared BLSO: Dy3+/Eu3+ phosphor can be proven as a potential color-tunable luminescent material for w-LEDs.