Luminescence property, energy transfer and thermal property of color tunable phosphor Ca9-wCe0.5Y0.5-x-y-z(PO4)7:xTb3+, yEu3+, zSm3+, wMn2+

Abstract

Abstract Series of Ca9-wCe0.5Y0.5-x-y-z(PO4)7:xTb3+, yEu3+, zSm3+, wMn2+ phosphors are synthesized by a high temperature solid state method. The spectral property and fluorescence decay curves are measured and used to demonstrate the energy transfer effect in Ce3+-Tb3+, Ce3+-Sm3+, Ce3+-Eu3+, Tb3+-Sm3+, Tb3+-Eu3+ and Tb3+-Mn2+. For Ca9Ce0.5Y0.5(PO4)7, the concentration of Ce3+ is higher and it can act as activator and sensitizer simultaneously. Ce3+ and Tb3+ can emit blue and green light under near ultraviolet excitation, respectively. Sm3+, Eu3+ and Mn2+ can produce red emission. In order to generate white light, Ce3+/Tb3+/Sm3+, Ce3+/Tb3+/Eu3+ and Ce3+/Tb3+/Mn2+ doped phosphors are investigated, and Ca8.8Ce0.5Y0.33(PO4)7:0.17Tb3+,0.20Mn2+ can create high quality white light. Its color rendering index can be high up to 80.2 and correlated color temperature is 4735\u202fK, and its thermal stability is high. The result indicates that the acquired phosphors can be potential for the use of ultraviolet excited white light emitting diodes.