Synthesis and optical properties of red/blue-emitting Sr2MgSi2O7:Eu 3 +/Eu 2+ phosphors for white LED

Title: Synthesis and optical properties of red/blue-emitting Sr2MgSi2O7:Eu 3 +/Eu 2+ phosphors for white LED
Authors: Tong, Thi Hao Tam
Nguyen, Duy Hung
Nguyen, Thi Kim Lien
Nguyen, Duc Trung Kien
Pham, Thanh Huy
Keywords: Sr2MgSi2O7:Eu 3+ /Eu 2+;Red and blue emitting phosphor;Photoluminescence
Issue Date: 2016
Publisher: ĐHQGHN
Abstract: Phosphor-converted white light emitting diodes (white LEDs) have received great attention in recent years since they have several excellent features such as high lumen output, low power consumption, long lifetime and environmentally friendly. In this work, we report the co-precipitation synthesis of red/blue Sr2MgSi2O7:Eu 3+ /Eu 2+ phosphors with various Eu doping concentration. The results show that the ob-tained Sr2MgSi2O7:Eu 3+ /Eu 2+ phosphors have good crystallinity and emit strong red (Sr2MgSi2O7:Eu 3+ ) and blue (Sr2MgSi2O7:Eu 2+) emissions under near UV light excitation. The sharp emission peaks at 577, 590, 612, 653, and 701 nm corresponded to the typical 5 D0/7 Fj (j=0,1,2,3,4) transitions of Eu 3+ , and the blue emission peaking at 460 nm is attributed to the typical 4f 6 5d 1 -4f 7 transition of Eu 2+ in the same Sr2MgSi2O7 host lattice. Both phosphors can be well excited in the wavelength range of 260- 400 nm where the near UV-LED is well matched. The above results suggest that the Sr2MgSi2O7:Eu 3+ /Eu 2+ phosphors are promising red/blue-emitting phosphors for the application in near UV pumped phosphor-converted white LEDs
Description: p. 204-208
URI: http://repository.vnu.edu.vn/handle/VNU_123/58331
ISSN: 2468-2284
Appears in Collections:Advanced Materials and Devices

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