Tri-chromatic white-light emission from a single-phase Ca9Sc(PO4)7:Eu(2+),Tb(3+),Mn(2+) phosphor for LED applications

A series of single-phase Ca9Sc(PO4)7:Eu(2+),Tb(3+),Mn(2+) phosphors for UV excitations were synthesized by a high-temperature solid-state reaction. Energy transfer from Eu(2+)→ Tb(3+) and Eu(2+)→ Mn(2+) in a Ca9Sc(PO4)7 sample is a feasible route to realize color-tunable emission because Ca9Sc(PO4)7 single-doped Eu(2+)/Tb(3+)/Mn(2+) emit blue, green and red light, respectively. Most of the white light region in the CIE chromaticity diagram has been realized in Ca9Sc(PO4)7:Eu(2+),Tb(3+),Mn(2+) phosphors. Warm white light including the points of (0.337, 0.331), (0.353, 0.355) and (0.358, 0.327) close to day light (0.33, 0.33) with CCT of 5285 K, 4719 K and 4333 K is obtained, respectively.