Potential single-phased white-emitting phosphor (Ca0.33Sr0.67)7(SiO3)6Cl2: Ce3+, Eu2+ for ultraviolet light-emitting diode

Abstract

A series of white-emitting and color temperature-tunable phosphors (Ca_0.33Sr_0.67)₇(SiO₃)₆Cl₂: Ce³⁺, Eu²⁺ have been synthesized by high temperature solid-state reaction. The photoluminescence emission and excitation spectra, and the lifetime are investigated in detail. The samples could display varied color emission from violet (0.1696, 0.0693) towards standard white (0.3314, 0.334) and ultimately to warm white (0.3773, 0.396) under excitation by 340 nm light by adjusting the relative proportion of Ce³⁺/Eu²⁺. The energy transfer mechanism from Ce³⁺ to Eu²⁺ in the (Ca_0.33Sr_0.67)₇(SiO₃)₆Cl₂ phosphors is dominated by the electric dipole–dipole interaction. These results indicate that the (Ca_0.33Sr_0.67)₇(SiO₃)₆Cl₂: Ce³⁺, Eu²⁺ phosphor might be promising as a single-phased white-light-emitting phosphor for UV LEDs.