Synthesis, structure and optical properties of cerium-doped calcium barium phosphate - a novel blue-green phosphor for solid-state lighting

A new blue-green phosphor, Ca 6 BaP 4 O 17 :Ce 3+ , which can be prepared by conventional solid-state synthesis, is reported as a candidate phosphor for solid-state lighting with near-ultraviolet LEDs. Under excitation at around 400 nm, Ca 6 BaP 4 O 17 :Ce 3+ shows strong blue-green emission with the peak position at 477 nm. Ce 3+ ,Si 4+ co-doping is found to enhance the luminous intensity, and the unique emission characteristics of this combination are studied and related to the crystal structure. Ca 6 BaP 4 O 17 is an exceptional host material, which also accommodates Eu 2+ , emitting strong yellow light under 400 nm excitation. A fabricated white LED, combining Ca 6 BaP 4 O 17 :Ce 3+ ,Si 4+ with Ca 6 BaP 4 O 17 :Eu 2+ and a red CaAlSiN 3 :Eu 2+ phosphor, achieved a luminous efficacy of 45 lm W −1 with a color-rendering index of 93 around the correlated color temperature of 4500 K. A new blue-green phosphor, Ca 6 BaP 4 O 17 :Ce 3+ , which can be prepared by conventional solid-state synthesis, is reported as a candidate phosphor for solid-state lighting with near-ultraviolet LEDs.