Protected-annealing regulated defects to improve optical properties and luminescence performance of Ce:YAG transparent ceramics for white LEDs

Sun, Bingheng1; Zhang, Le1,2,3; Zhou, Tianyuan1,2; Shao, Cen1; Zhang, Lei4; Ma, Yuelong1,5; Yao, Qing1,5; Jiang, Zhigang1,5; Selim, Farida A.2; Chen, Hao1

2019-04-14

10.1039/c8tc06600k

Journal of Materials Chemistry C   影响因子和分区

2050-7526

2050-7534

Ce:YAG transparent ceramic, a promising photo-converter for white LED lighting, faces a significant obstacle of post-annealing treatments, which allow the simultaneous elimination of defections and the regulation of the redox state of Ce. In this paper, vacuum as-sintered high quality Ce:YAG ceramics were subjected to various annealing conditions, and their microstructural evolution, and optical and luminescence properties were monitored and studied systematically. The results showed that air annealing efficiently benefited the microstructure and optical transmittance. In addition, the absorption band below 300 nm was strongly dependent on the annealing strategies due to the elimination of defects (e.g. F/F+-type color centers) and charge transfer (CT) between Ce(III) and Ce(IV). By constructing with 1350 degrees C air annealed Ce:YAG ceramics, a high-performance white LED with a luminous efficiency radiation (LER) exceeding 220 lm W-1 was achieved, thanks to the "protected"-annealing condition, which guaranteed moderate CT from Ce(IV) to Ce(III) due to weakened pump light absorption by defects. Differing from traditional Ce:YAG phosphors, excrescent oxygen vacancies were introduced by annealing Ce:YAG ceramics in hydrogen, leading to deteriorated luminescence properties. Therefore, it is expected that this refined preparation of Ce:YAG photo-convertors could drive the development of white LED lighting.

SCI ; EI

英语

其他

project of aqueous tape for ultra-thin layered MLCC applications[GRCK2017042411005977]

Materials Science ; Physics

Materials Science, Multidisciplinary ; Physics, Applied

WOS:000464424100037

ROYAL SOC CHEMISTRY

20191506767178

Annealing ; Ceramic materials ; Charge transfer ; Color centers ; Light absorption ; Light emitting diodes ; Luminescence of inorganic solids ; Optical properties ; Yttrium aluminum garnet

Heat Treatment Processes:537.1 ; Semiconductor Devices and Integrated Circuits:714.2 ; Light/Optics:741.1 ; Chemical Reactions:802.2 ; Ceramics:812.1 ; Crystalline Solids:933.1

Web of Science

1.Jiangsu Normal Univ, Sch Phys & Elect Engn, Jiangsu Key Lab Adv Laser Mat & Devices, Xuzhou 221116, Jiangsu, Peoples R China
2.Bowling Green State Univ, Dept Phys & Astron, Bowling Green, OH 43403 USA
3.Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA
4.Southern Univ Sci & Technol, SUSTech Acad Adv Interdisciplinary Studies, Shenzhen 518055, Peoples R China
5.Jiangsu Univ, Sch Mech Engn, Zhenjiang 212013, Jiangsu, Peoples R China

Sun, Bingheng,Zhang, Le,Zhou, Tianyuan,et al. Protected-annealing regulated defects to improve optical properties and luminescence performance of Ce:YAG transparent ceramics for white LEDs[J]. Journal of Materials Chemistry C,2019,7(14):4057-4065.

Sun, Bingheng.,Zhang, Le.,Zhou, Tianyuan.,Shao, Cen.,Zhang, Lei.,...&Chen, Hao.(2019).Protected-annealing regulated defects to improve optical properties and luminescence performance of Ce:YAG transparent ceramics for white LEDs.Journal of Materials Chemistry C,7(14),4057-4065.

Sun, Bingheng,et al."Protected-annealing regulated defects to improve optical properties and luminescence performance of Ce:YAG transparent ceramics for white LEDs".Journal of Materials Chemistry C 7.14(2019):4057-4065.