Synthesis, structure and photoluminescence properties of Ca2LuHf2(AlO4)3: Ce3+, a novel garnet-based cyan light-emitting phosphor

A novel garnet phosphor, Ca2LuHf2(AlO4)(3): Ce3+ (CLHA:Ce3+), was successfully designed and synthesized using a solid-state method. Its crystal structure, band structure and photoluminescence properties were investigated in detail. Under n-UV excitation, CLHA:Ce3+ exhibited cyan to blue-green emission depending on the Ce3+ concentration. The QE of the optimal sample was 50.3%. The concentration quenching mechanism of the Ce3+ emission was dominated by dipole-dipole interactions. A novel method to obtain white light was developed by combining the CLHA:Ce3+ phosphor with a CaAlSiN3: Eu2+ red phosphor. Both the emission intensity and thermal stability of CLHA:Ce3+ were found to be superior to those of the commercial (Sr, Ba)(2)SiO4:Eu2+ phosphor. All of the results indicate the CLHA:Ce3+ phosphor to be a promising candidate for application in white LEDs.