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Design of a Yellow-Emitting Phosphor with Enhanced Red Emission via Valence State-control for Warm White LEDs Application.

ABSTRACT: The phosphor-converted warm W-LED have being rapidly developed due to the stringent requirements of general illumination. Here, we utilized a strategy to synergistically enhance the red region and emission intensity of novel Eu-activated yellow-emitting LaSiO2N phosphors. This was realized by predicting optimum crystal structure, and governing the concentration of doping ions as well as preparation temperature. By using these straight-forward methods, we were able to vary the valence to enhance the red region and improve the quantum efficiency of LaSiO2N phosphor. The warm W-LED lamp fabricated with this red region enhanced LaSiO2N:Eu phosphor exhibited high CRI (Ra?=?86), suitable CCT (5783?K) and CIE chromaticity (0.33, 0.36), indicating this synergistically enhanced strategy could be used for design of yellow-emitting phosphor materials to obtain warm W-LEDs.

SUBMITTER: Chen J

PROVIDER: S-EPMC4980616 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Design of a Yellow-Emitting Phosphor with Enhanced Red Emission via Valence State-control for Warm White LEDs Application.

Chen Jian J Liu Yangai Y Mei Lefu L Peng Peng P Cheng Qijin Q Liu Haikun H

Scientific reports 20160811

The phosphor-converted warm W-LED have being rapidly developed due to the stringent requirements of general illumination. Here, we utilized a strategy to synergistically enhance the red region and emission intensity of novel Eu-activated yellow-emitting LaSiO2N phosphors. This was realized by predicting optimum crystal structure, and governing the concentration of doping ions as well as preparation temperature. By using these straight-forward methods, we were able to vary the valence to enhance ...[more]

PMID: 27510501

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