Investigations on luminescence of CaLa4Si3O13-based phosphors for multifunctional applications

To develop novel luminescent materials for multifunctional applications, CaLa4Si3O13 (CLSO)-based phosphors were prepared by solid-state reaction method. Firstly, the tunable-emission was obtained in the Tb3+-Mn2+ codoped CLSO, and the energy transfer from Tb3+ to Mn2+ was also found. The luminescence thermal stability for CLSO:0.8Tb3+,0.07Mn2+ reveals that the emission intensity of Mn2+ decays faster than that of Tb3+ with increasing temperature, resulting in the changing emission color. This observation indicates that the CLSO:Tb3+,Mn2+ could introduce a potential technique for temperature measurement. Secondly, the CLSO:0.05Eu3+,zY3+ phosphors reveal that the emission intensity and color both change with Y3+ concentration, and the optimal Y3+ concentration was determined for z = 0.8. This phosphor could apply to white LEDs. Thirdly, the upconversion luminescence upon 980 nm excitation was observed in the CLSO:Yb3+,Er3+, CLSO:Yb3+,Ho3+, and CLSO:Yb3+,Tm3+ phosphors. Green and red emissions were gained in the Yb3+-Er3+ and Yb3+-Ho3+ doped CLSO, respectively. Very strong near-infrared emission was generated in the Yb3+-Tm3+ doped CLSO and the visible emission is almost quenched relative to the near-infrared emission.