Novel red perovskite phosphor Ca2AlNbO6:Eu3+ for white light-emitting diode application

Eu3+-doped perovskite phosphors of Ca2AlNbO6 were synthesized from a solid state reaction. A small amount of the Li2CO3 flux was found to greatly shorten calcination time and reduce reaction temperature. The structural and optical properties of the samples were systematically investigated. The excitation spectra of Ca2AlNbO6:Eu3+ reveal two excitation bands at 398 (7F0→5L6) and 466 nm (7F0→5D2), which match well with the two popular emissions from near-UV and blue LED chips. Under blue light excitation, the red emission of Ca2AlNbO6:0.05Eu3+ is twice more intense than that of (Y0.95Eu0.05)2O3. The chromaticity coordinates of (Ca0.95Eu0.05)2AlNbO6 (x=0.654, y=0.346) are close to the standard values (x=0.670, y=0.330) of National Television Standard Committee (NTSC). The optical properties suggest that Ca2AlNbO6:Eu3+ is an efficient red-emitting phosphor for light-emitting diode applications.