Fabrication and photoluminescence characteristics of novel red-emitting Ba2LuNbO6:Eu3+ double-perovskite phosphors on near UV WLEDs

Red emitting phosphors play a significant role in accelerating the improvement of illumination quality for white light emitting diodes(WLEDs).In this work,by using solid-state reaction method,an efficient novel Ba2LuNbO6:Eu3+phosphor with double-perovskite structure was successfully prepared.Here,a series of Ba2LuNbO6:Eu3+red phosphors can be efficiently pumped by the near-ultraviolet(UV) light and then present high-brightness at orange emission(598 nm,~5D0→~7 F1) and red emission(610 nm,~5D0→~7 F2).The ratio values of 610 to 598 nm in Ba2LuNbO6:Eu3+phosphors exceed 1 when the content of Eu3+is larger than 0.4 mol,because the occupation of Eu3+ions is changed from Lu3+ions with symmetric sites to Ba2+ions with asymmetric sites.Besides,the optimized concentration of Eu3+at the~5D0→~7 F2transitions is obtained when x=1,indicating that there is non-concentration quenching in Ba2LuNbO6:Eu3+phosphors.Moreover,the CIE chromaticity coordinates of Ba2LuNbO6:Eu3+was calculated to be(0.587,0.361),the color purity was calculated to be 72.26% and internal quenching efficiency(IQE) was measured to be 67%.Finally,the thermal stability of Ba2LuNbO6:Eu3+phosphors was also studied.Our work demonstrates that the novel double-perovskite red-emitting Ba2LuNbO6:Eu3+phosphors are prospective red emitting elements for WLEDs applications.