Synthesis, structure and luminescent properties of yellow phosphor La3Si6N11:Ce3+ for high power white-LEDs

A series of high phase purity blue light excitable yellow-emitting La3−xSi6N11:xCe3+ phosphors were synthesized by the high temperature solid state reactions method. The structure and luminescent properties were investigated. The phase structure was studied by means of X-ray diffraction, structures refinements and energy dispersive X-ray spectroscopy. The phosphors effectively excited by the light of 450 nm and show intense yellow emission at 535 nm with FWHM of 115 nm corresponding to the 5d → 2F5/2 and 5d → 2F7/2 transitions of Ce3+. In addition, the optimized La2.86Si6N11:0.14Ce3+ exhibits a weak thermal quenching, which remains 98.2% of the initial emission intensity when heated to 200 °C, the thermal quenching properties exhibit a modest decline when the temperature returned to room temperature. The above results indicate that La3Si6N11:Ce3+ can be regarded as a high promising phosphor for applications in high power white-light LED.