Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED

To address the issue of the lack of red light in traditional Ce<sup>3+</sup>: YAG-encapsulated blue LED white light systems, we utilized spark plasma sintering (SPS) to prepare spinel-based Cr<sup>3+</sup>-doped red phosphor ceramics. Through phase and spectral analysis, the...

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Main Authors: Wenchao Ji, Xueke Xu, Ming Qiang, Aihuan Dun
Format: Article
Language:English
Published: MDPI AG 2024-04-01
Series:Materials
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Online Access:https://www.mdpi.com/1996-1944/17/7/1610
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author Wenchao Ji
Xueke Xu
Ming Qiang
Aihuan Dun
author_facet Wenchao Ji
Xueke Xu
Ming Qiang
Aihuan Dun
author_sort Wenchao Ji
collection DOAJ
description To address the issue of the lack of red light in traditional Ce<sup>3+</sup>: YAG-encapsulated blue LED white light systems, we utilized spark plasma sintering (SPS) to prepare spinel-based Cr<sup>3+</sup>-doped red phosphor ceramics. Through phase and spectral analysis, the SPS-sintered ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> phosphor ceramic exhibits good density, and Cr<sup>3+</sup> is incorporated into [AlO<sub>6</sub>] octahedra as a red emitting center. We analyzed the reasons behind the narrow-band emission and millisecond-level lifetime of ZAO: 0.5%Cr<sup>3+</sup>, attributing it to the four-quadrupole interaction mechanism as determined through concentration quenching modeling. Additionally, we evaluated the thermal conductivity and thermal quenching performance of the ceramic. The weak electron-phonon coupling (EPC) effects and emission from antisite defects at 699 nm provide positive assistance in thermal quenching. At a high temperature of 150 °C, the thermal conductivity reaches up to 14 W·m<sup>−1</sup>·K<sup>−1</sup>, and the 687 nm PL intensity is maintained at around 70% of room temperature. Furthermore, the internal quantum efficiency (IQE) of ZAO: 0.5%Cr<sup>3+</sup> phosphor ceramic can reach 78%. When encapsulated with Ce<sup>3+</sup>: YAG for a 450 nm blue LED, it compensates for the lack of red light, adjusts the color temperature, and improves the color rendering index (R9). This provides valuable insights for the study of white light emitting diodes (WLEDs).
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spelling doaj.art-9418787024a644d992ebcb5e80b0c2ee2024-04-12T13:22:07ZengMDPI AGMaterials1996-19442024-04-01177161010.3390/ma17071610Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLEDWenchao Ji0Xueke Xu1Ming Qiang2Aihuan Dun3Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, No. 899 Huiwang East Road, Shanghai 201800, ChinaShanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, No. 899 Huiwang East Road, Shanghai 201800, ChinaShanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, No. 899 Huiwang East Road, Shanghai 201800, ChinaShanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, No. 899 Huiwang East Road, Shanghai 201800, ChinaTo address the issue of the lack of red light in traditional Ce<sup>3+</sup>: YAG-encapsulated blue LED white light systems, we utilized spark plasma sintering (SPS) to prepare spinel-based Cr<sup>3+</sup>-doped red phosphor ceramics. Through phase and spectral analysis, the SPS-sintered ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> phosphor ceramic exhibits good density, and Cr<sup>3+</sup> is incorporated into [AlO<sub>6</sub>] octahedra as a red emitting center. We analyzed the reasons behind the narrow-band emission and millisecond-level lifetime of ZAO: 0.5%Cr<sup>3+</sup>, attributing it to the four-quadrupole interaction mechanism as determined through concentration quenching modeling. Additionally, we evaluated the thermal conductivity and thermal quenching performance of the ceramic. The weak electron-phonon coupling (EPC) effects and emission from antisite defects at 699 nm provide positive assistance in thermal quenching. At a high temperature of 150 °C, the thermal conductivity reaches up to 14 W·m<sup>−1</sup>·K<sup>−1</sup>, and the 687 nm PL intensity is maintained at around 70% of room temperature. Furthermore, the internal quantum efficiency (IQE) of ZAO: 0.5%Cr<sup>3+</sup> phosphor ceramic can reach 78%. When encapsulated with Ce<sup>3+</sup>: YAG for a 450 nm blue LED, it compensates for the lack of red light, adjusts the color temperature, and improves the color rendering index (R9). This provides valuable insights for the study of white light emitting diodes (WLEDs).https://www.mdpi.com/1996-1944/17/7/1610phosphor ceramicWLEDspinelCr<sup>3+</sup>
spellingShingle Wenchao Ji
Xueke Xu
Ming Qiang
Aihuan Dun
Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED
Materials
phosphor ceramic
WLED
spinel
Cr<sup>3+</sup>
title Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED
title_full Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED
title_fullStr Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED
title_full_unstemmed Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED
title_short Spinel-Based ZnAl<sub>2</sub>O<sub>4</sub>: 0.5%Cr<sup>3+</sup> Red Phosphor Ceramics for WLED
title_sort spinel based znal sub 2 sub o sub 4 sub 0 5 cr sup 3 sup red phosphor ceramics for wled
topic phosphor ceramic
WLED
spinel
Cr<sup>3+</sup>
url https://www.mdpi.com/1996-1944/17/7/1610
work_keys_str_mv AT wenchaoji spinelbasedznalsub2subosub4sub05crsup3supredphosphorceramicsforwled
AT xuekexu spinelbasedznalsub2subosub4sub05crsup3supredphosphorceramicsforwled
AT mingqiang spinelbasedznalsub2subosub4sub05crsup3supredphosphorceramicsforwled
AT aihuandun spinelbasedznalsub2subosub4sub05crsup3supredphosphorceramicsforwled