A promising red-emitting phosphor Li2Eu4(MoO4)7 prepared by sol–gel method

• Li2Eu4(MoO4)7 phosphor was synthesized by a sol-gel method for the first time.
• The chromaticity coordinate of Li2Eu4(MoO4)7 (0.6497, 0.3499) is better than that of Y2O2S:Eu2+ (x = 0.63, y = 0.35).
• The Li2Eu4(MoO4)7’s decay lifetime is shorter than LiGd(MoO4)2:Eu3+, KLu(MoO4)2:Eu3+ and Y2O3:Eu3+ phosphors’.

A series of red light-emitting phosphors Li2Y4-x(MoO4)7:xEu3+ were synthesized by a sol-gel method. These samples were characterized by DSC-TGA, XRD, PL and FE-SEM analysis. The best dosage of citric acid is four times of metal ions. The optimal sintering temperature is 900 °C. The luminescence intensity of Li2Y4-x(MoO4)7:xEu3+ are strongest when the doping concentration of Eu3+ is 4 mol. These phosphors can be excitated by near-UV light of 395 nm and blue light of 465 nm effectively, and show strong red light at 615 nm, which is corresponding to 5D0 → 7F2 transition of Eu3+ ion. The CIE chromaticity coordinates of Li2Eu4(MoO4)7 phosphor is calculated to be (0.6497, 0.3499), and its lifetime is 0.38 ms. The results show that the phosphor is a promising red component candidate for near-UV and bule LED application.

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