OPTICS EXPRESS
·
2023
·Vol. 31
·期 15
·24914-24925
·
IF 3.8
Zitong Liu,Le Zhang,Le Zhang,Le Zhang,Le Zhang,Jian Kang,Jian Kang,Tianyuan Zhou,Tianyuan Zhou,Shiwei Chen,Shiwei Chen,Peng Yang,Bingheng Sun,Yang Li,Hao Chen,Hao Chen,Hao Chen
Ceramic phosphors are widely considered the next-generation phosphor material for white LED/LD lighting, and a wide spectrum is a key factor in improving the CRI of lighting sources. In this paper, a novel, to our knowledge, barcode-structured YAG:Ce/YAG:Ce,Mn ceramic phosphor was designed and fabricated. The lighting sources with the CRI value of 73.5 and 68.9 were obtained under the excitation of blue LEDs and blue LDs, respectively. Simultaneously, thanks to the effective supplementary emission from a red LD, the CRI of the ceramic-based lighting source reached 81.8 under blue LD excitation. Specifically, the microstructure and luminescent property of ceramic phosphors with different thicknesses and ion doping concentrations were systematically studied. Besides, by changing the blue power from 0.52 W to 2.60 W, the CCT of the laser lighting source with the encapsulation of optimized YAG:Ce/YAG:Ce,Mn ceramic phosphors ranged from 3928 K to 5895 K, while the CRI always maintained above 80. The above results indicate that barcode-structured Ce:YAG/Ce,MnYAG ceramic phosphor is a candidate to achieve a high CRI and ican be applied to various lighting occasions.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Xu Changyi,Ding Haifeng,Fan Guohua,Zhou Tianliang,Zhou Wenbin
Al 2 O 3 -based YAG:Ce PiG composite films have gained significant attention as optimal color converters for laser illumination due to their straightforward fabrication process and exceptional stability. However, the inherent limitations in the thermal conductivity of Al 2 O 3 result in a low pump utilization rate, making it challenging to achieve efficient white light output from PiG films. In this study, we introduce a novel laser illumination component composed of porous stainless steel (PSS) integrated with YAG:Ce/glass (PGiPSS), which has been sintered at 750 °C. The PSS demonstrates adequate thermal conductivity and the capacity to host a substantial number of luminescent particles within its pores, leading to enhanced quantum efficiency and reduced thermal quenching effects. Notably, when subjected to a 450 nm laser diode with a peak excitation power density of 24.10 W/mm 2 , the developed PGiPSS generated white light with a correlated color temperature (CCT) of 6693 K and an impressive luminous efficiency of 135.2 lm/W. These findings indicate that PGiPSS is a viable candidate for applications requiring high-power and high-brightness laser illumination.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Yun Tang,Ben Liu,Nan Yan,Xiaoqiang He,Hudie Yuan,Yalou Xin,Hongfeng Yin
Widespread application of YAG:Ce-based white light-emitting diodes (WLEDs) is being challenged due to the lack of red emission, leading to their poor color rendering index (Ra) and high correlated color temperature (CCT). Perovskite quantum dots (QDs), presenting high photoluminescence quantum yield and simple fabrication process have been recognized as promising red-emitting component for warm WLEDs. However, conventional method by mechanically mixing QDs with YAG:Ce always results in undesirable dispersion due to their huge size difference. Moreover, the two components display different sinking behavior in silicone , which would further deteriorate the color uniformity of WLED. To address these issues, in this study, red-emitting MAPbBr 3-x I x QDs-coated YAG:Ce (A-YAG@QDs) composites were successfully prepared to further fabricate WLED with compensated red emission. The chemical coordination interactions between QDs and functionalized YAG:Ce make the two components behave as a whole, which effectively avoids the dispersion and sinking-related issues. The WLED, which combined blue LED chip and A-YAG@QDs composite, exhibited warm white light with low CCT of 4474 K, high Ra of 90.1 and high value of saturated red color component R9 as 95. This study demonstrated a promising strategy to prepare QDs-coated phosphor composites for the generation of warm white light for indoor lighting application.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2021
·
IF 3.712
Yaqian Zhang,Jianming Liu,Yujie Zhang,Haisheng Yang,Yanxia Yu,Qingyun He,Xiaojuan Liang,Yongfu Liu,Weidong Xiang
At present, solid-state laser-driven lighting fabricated with blue laser diode (LD) and phosphor has been greatly developed in high-power lighting applications. The major obstacle is the luminescence saturation threshold of the fluorescence conversion material (YAG:Ce). In this work, we successfully prepared a series of high-quality and robust YAG:Ce single crystals . With high quantum efficiency (QE = 92%), regular crystal structure and high thermal conductivity , the single-crystal has excellent ability to deal with high radiation flux and thermal accumulation generated by high power. Matching the single-crystal with the laser, the luminous efficiency up to 274 lm/W and saturation threshold of 12 W/mm 2 were obtained. In addition, the influence of Ce doping concentration and sample processing conditions on the indicators in laser-driven white lighting was systematically studied. The results are of great significance and are believed to promote the development of solid-state laser-driven lighting.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
OPTICS EXPRESS
·
2024
·Vol. 32
·期 2
·1465-1477
·
IF 3.2
Xu Chen,Mingyuan Liu,Chunming Zhou,Chunming Zhou,Hang Chen,Tianyuan Zhou,Tianyuan Zhou,Yanbin Li,Yanbin Li,Shenghui Lin,Cong Wei,Cen Shao,Cen Shao,Guannan Chen,Guannan Chen,Jian Kang,Jian Kang,Pengde Han,Wieslaw Strek,Hao Chen,Hao Chen,Le Zhang,Le Zhang,Le Zhang,Le Zhang
High power and high brightness laser lighting puts forward new requirements for phosphor converters such as high luminous efficiency, high thermal conductivity and high saturation threshold due to the severe thermal effect. The structure design of phosphor converters is proposed as what we believe to be a novel strategy for less heat production and more heat conduction. In this work, the rod-shaped YAG:Ce phosphor ceramics (PCs) and disc-shaped YAG:Ce PCs as control group were fabricated by the gel casting and vacuum sintering, to comparatively study the luminescence performance for LD lighting, on the premise that the total number of transverse Ce3+ ions and the volume of samples from two comparison groups were same. All rod YAG:Ce PCs with low Ce3+ concentration exhibited the high luminous efficiency and better thermal stability than YAG:Ce discs with high Ce3+ concentration. Under the laser power density of 47.8 W/mm2, the luminous saturation was never observed in all rod-shaped YAG:Ce PCs. The high luminous efficacy of 245∼274 lm/W, CRI of 56.3∼59.5 and CCT of 4509∼4478 K were achieved. More importantly, due to the extremely low Ce3+ doping concentration (0.01 at%), rod-shaped ceramics based LDs devices showed the excellent thermal performance and their surface temperatures were even below 30.5 °C surprisingly under the laser power density of 20.3 W·mm-2 (2 W). These results indicate that the rod shape of phosphor converter is a promising structure engineering for high power laser lighting.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2022
·Vol. 10
·期 42
·16147-16156
·
IF 8.067
Hailiang Fang,Beiying Zhou,Jiancheng Wang,Xiaobo Hu,Zesheng Pan,Shengjie Fan,Ping Huang,Shijia Gu,Lianjun Wang,Wan Jiang
Due to high thermal conductivity and excellent laser irradiation resistance, composite phosphor ceramics (CPCs) have been widely acknowledged as ideal color converters in laser lighting. However, achieving high-efficiency laser lighting is significantly limited by the inefficient utilization of pumping light. Microstructural tailoring is recognized as a promising strategy to improve the light extraction efficiency, while it is restricted by the harsh preparation conditions. Herein, we propose a novel Y2O3-YAG:Ce CPC controllably prepared from mesoporous Y2O3 powders and YAG:Ce phosphors using spark plasma sintering at a low temperature of 1160 °C. Attributed to the introduced Rayleigh scattering centers tailored by fine ceramic grains and well-matching of refractive indexes between the phosphor and the matrix, the Y2O3-YAG:Ce CPC exhibits an ultra-high relative internal quantum efficiency of 107% compared to that of the YAG:Ce phosphor. Impressively, when irradiated under a 450 nm laser diode, the as-prepared CPC produces white light with a high luminous efficiency of 178.42 l m W−1 and a low correlated color temperature of 4638 K, reflecting the enhanced light conversion efficiency. Furthermore, the CPC presents a remarkable improvement in thermal stability (only 6% luminescence loss at 200 °C) and is able to withstand a high laser flux density up to 6.16 W mm−2. These results demonstrate that the optimized Y2O3-YAG:Ce CPCs with designed microstructures are well suited for solid-state laser lighting with high power and brightness.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Qi Qiu,Manjie Huang,Weimeng Zheng,Chaoyan Xuan,Yong Wan,Bo Zhang,Zhongkuan Luo,Weizhong Lv
Systematic study on the impact of the pH value was performed in the preparation of YAG:Ce nanophosphor powders by reverse titration method. Therefore, we used wider range of the pH values from 5.0 to 8.3 for the synthesis, correlating closely with ratio R of the total metal ions to precipitant ammonium hydrocarbonate in the solution from 1:3 to 1:9. The calcination temperatures of 1050 °C and 1300 °C were tested for the crystallization of YAG:Ce nanophosphors. Acidic condition is more preferable for improved YAG:Ce nanophosphors through XRD spectra analysis for the type of crystals and the crystal size. The molar ratio Y 3+ /Al 3+ in the precursor was controlled at the level of R =1:3 to keep the stoichiometric ratio of YAG:Ce. SEM images showed the YAG:Ce nanophosphors prepared at acidic condition having smaller crystal size and improved dispersibility. Fluorescence spectrum displayed much stronger emission at R =1:3. The molar ratio R is a vital factor to control the quality of the YAG:Ce powders. The nanophosphors prepared at R =1:3 possessed the best fluorescence emission.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Chunming Zhou,Hang Chen,Yue Cao,Yanbin Li,Tianyuan Zhou,Chaofan Shi,Dongshun Chen,Xu Chen,Shenghui Lin,Xuanchu Liu,Jian Kang,Cen Shao,Wieslaw Strek,Hao Chen,Le Zhang
Phosphor converters with excellent thermal performance and high color rendering index (CRI) demonstrate vast application prospects in the field of laser diodes (LDs) lighting. Nevertheless, the significant heat accumulation within the converters and the absence of red spectral components pose challenges in achieving both a high saturation threshold and a high CRI for Y 3 Al 5 O 12 :Ce phosphor converters destined for white LDs. In this work, Mg 2 Al 4 Si 5 O 18 :Eu/Y 3 Al 5 O 12 :Ce (MAS:Eu/YAG:Ce) composite phosphor converters with excellent thermal performance and enhanced CRI were designed and fabricated for reflective laser lighting. Impressively, MAS:Eu/YAG:Ce phosphor-glass-ceramic composites (PGCC) retained a remarkable 97.8 % of the room temperature emission intensity at 150 °C. The reasons for this could be attributed to the strong thermal quenching resistance exhibited by MAS:Eu phosphors, as well as the ultra-thin glass bonding layer of about 150–200 μm. Meanwhile, by integrating the MAS:Eu/YAG:Ce PGCC with a 450 nm laser source, white LD devices operating in a remote excitation mode were fabricated. These white LDs demonstrated an improved CRI of 76 and maintained a low surface temperature of 131.7 °C under an ultra-high laser power density of 47.8 W/mm 2 (laser power ∼ 4.70 W). Moreover, the maximum luminous flux and luminous efficiency of the white LDs were 484 lm and 103 lm/W, respectively. Therefore, the design of MAS:Eu/YAG:Ce composite phosphor converters offers a new approach for the development of high-power white LDs.
研究领域:
光学材料
·
照明工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Yun Tang,Xiaoqiang He,Yuchao Zhang,Hudie Yuan,Yalou Xin,Xiaohu Ren,Qiang Chen,Hongfeng Yin
Widespread application of YAG:Ce-based white light-emitting diodes (WLEDs) is being challenged for their poor color rendering index (CRI) and high correlated color temperature (CCT) due to the lack of red emission. Organic-inorganic hybrid perovskite nanocrystals (MAPbX 3 PNCs, X = Cl, Br, I or mixture of them), presenting high photoluminescence quantum yield, tunable emission color and simple fabrication process have been recognized as promising red-emitting component for warm WLEDs. However, additional protection process for PNCs always needed due to their poor stability, which complicates the fabrication procedures of WLEDs. Besides, nano-sized PNCs and micron YAG:Ce powder display different sinking behavior in silicone , which also hard to ensure the uniform distribution of the two components and subsequently stable optical characteristics of the device. Herein, a one-pot anchoring strategy is implemented to realize the enhanced thermal and photo-stabilities of in-situ generated red-emitting MAPbBr 0.5 I 2.5 PNCs and simultaneously strong interaction between the PNCs and YAG:Ce to form PNCs@A-YAG composite, which greatly simplifies the processes, and also avoids the uneven distribution of phosphor and PNCs in silicone . Furthermore, the WLED, fabricated by PNCs@A-YAG and a commercial blue chip, exhibits high CRI of 92, low CCT of 4755 K, and super high saturated red color R9 of 95, which are of vital importance in achieving warm white light for indoor lighting applications. This work could promote the practical application of perovskite nanocrystals in the field of high color rendering index WLEDs.
研究领域:
材料科学
·
光学工程
·
电子器件
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2019
·Vol. 7
·期 13
·3901-3908
·
IF 6.641
Jinchun Wang,Xueyuan Tang,Peng Zheng,Shuxing Li,Tianliang Zhou,Rong-Jun Xie
Achieving super-high brightness laser-driven solid state lighting in a transmissive mode is significantly limited by the thermal robustness and light extraction efficiency of color converter materials. Therefore, it is a must to enhance the thermal conductivity and conversion efficiency of color converters by appropriate compositional design and microstructural tailoring. In this work, we propose thermally self-managing YAG:Ce–Al2O3 composite ceramic color converters that consist of luminescent YAG:Ce phosphor particles embedded in a thermally conductive Al2O3 matrix, which allows them to be combined with high-power blue laser diodes to create super-high brightness white laser-driven light without using any heat sink. The thermal conductivity of the ceramic color converters increases linearly from 10.2 to 32.5 W m−1 K−1 as the Al2O3 content varies from 0 to 90 wt%. Impressively, the composite ceramic with 60 wt% Al2O3 can withstand an incident laser power density of up to 20.1 W mm−2. A high-brightness white laser-driven light is obtained with a luminance of 982 Mcd m−2. Moreover, the secondary Al2O3 particles also act as scattering centers and enhance the light conversion efficiency. A maximum luminous efficacy of 157 lm W−1 is achieved under 11.94 W mm−2 blue laser excitation at an Al2O3 content of 24 wt%, increased by 27.3% compared to the Al2O3-free YAG:Ce ceramic. The as-designed YAG:Ce–Al2O3 phosphor ceramics thus validate their great suitability in high-power and high-brightness laser-driven solid-state lighting.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·Vol. 13
·期 9
·4781-4790
·
IF 5.1
Hailiang Fang,Lei Li,Beiying Zhou,Weijie Li,Shijia Gu,Qi Zheng,Lianjun Wang,Wan Jiang
Composite phosphor ceramics (CPCs) have found extensive applications in high-power, high-brightness LD lighting, primarily due to their superior thermal conductivity, stability and microstructural tailorability. However, the high sintering temperatures and refractive index mismatches of CPCs impose a significant impact on their luminous efficacy and practical application. To address these challenges, this study introduces a novel approach utilizing reactive spark plasma sintering of mesoporous Y2O3 and Al2O3 powders and YAG:Ce phosphors. This approach leverages the enhanced driving forces stemming from mesoporous structure collapse and phase transformation, enabling the rapid preparation of dense polycrystalline YAG–YAG:Ce CPCs at a significantly reduced sintering temperature of 1350 °C and a short holding time of 3 minutes. Owing to the minimal refractive index difference and designed differential grain sizes, the resultant CPC exhibits a high internal quantum efficiency of 83.8%, which approaches 95.6% of that observed in YAG:Ce phosphors. When subjected to irradiation by a 450 nm laser diode, the as-prepared CPC produces white light with a remarkable luminous efficacy of 202.13 lm W−1 and a low correlated color temperature of 5298 K, highlighting the enhanced light conversion efficiency. Furthermore, the CPC presents a substantial enhancement in thermal stability, experiencing only a 6% luminescence loss at 200 °C, and could endure a high laser flux density of up to 6.68 W mm−2. These results demonstrate that the optimized YAG–YAG:Ce CPCs are well suited for solid-state laser lighting, and contribute to the ongoing advancement of next-generation lighting technologies.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xiaolong Zhang,Kailong Ma,Shuo Wang,Pengchong Zhang,Lei Wu,Pengfei Li,Jinsheng Li,Xiwei Qi
The inadequate dissipation of heat and the suboptimal color quality of phosphor converters have been identified as critical constraints in the implementation of laser-driven lighting technology. In recent years, laser lighting has attracted significant attention as a pivotal direction for next-generation illumination systems. However, the thermal quenching effect induced by high-power blue laser sources significantly reduces the emission efficiency of phosphors, presenting a critical challenge that demands urgent resolution. In this study, we successfully fabricated AlN-YAG:Ce composite amorphous spheres by using the non-container solidification technique. The theoretical thermal conductivity of the glass-ceramic with 15 wt% AlN added was 23.13 W/(m∙K). Addressing the inherent limitation of weak luminescent properties in amorphous materials, crystallization treatment was implemented while preserving their advantageous characteristics. The amorphous crystallization treatment was found to be a successful method of achieving controllable optimization of high-efficiency luminescent performance. This objective was achieved through significantly enhancing emission efficiency via localized crystallization (formation of nanocrystalline or microcrystalline structures) in amorphous materials. Through systematic optimization and evaluation, the 15% AlN-YAG:Ce crystallized at 951 °Cglass-ceramic sample with an optimized thickness of 1 mm exhibited exceptional performance: under 1 W/mm 2 blue laser excitation, it achieved a luminous efficacy of 335.3 lm/W with a blue light absorptivity of 89.7% and a low correlated color temperature of 4405.4 K. The technology employed for the composite glass-ceramic's preparation offers a novel solution for the advancement of laser lighting technology.
研究领域:
材料科学
·
光学工程
·
固态照明
·
陶瓷材料
·
光子学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）