Luminescence and decay behavior of divalent europium activated barium borophosphate polycrystalline ceramics in the temperature regime 10–525 K

The luminescence properties of Ba3BP3O12 doped with divalent Eu2+ are investigated in the temperature range 10–525 K. Excitation and emission bands corresponding to f–d transition of Eu2+ from two crystallographic sites are identified. The PL spectra of Ba2.99Eu0.01BP3O12 sample at low temperatures further imply that the Eu2+ emission emanates from two different crystallographic sites for Ba2+ ions. The temperature dependence of emission intensity and lifetimes are studied. The luminescence intensity of Eu II does not have drastic decrease in the temperature range between 10 and 300 K, while that of Eu I decreases dramatically. Unfortunately, Ba2.99Eu0.01BP3O12 sample has poor thermal stability at temperatures higher than 300 K. The quantum yield, activation energy and thermal quenching mechanism of the luminescence are also discussed.