New strategy for designing orangish-red-emitting phosphor via oxygen-vacancy-induced electronic localization
| Autor: | Dayong Jin, Peipei Dang, Gongcheng Xing, Kang Liu, Min Liu, Sisi Liang, Guogang Li, Yi Wei, Jun Lin, Ziyong Cheng |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
lcsh:Applied optics. Photonics
Photoluminescence chemistry.chemical_element Germanium Phosphor 02 engineering and technology 01 natural sciences Article law.invention 010309 optics law 0103 physical sciences Activator (phosphor) lcsh:QC350-467 business.industry lcsh:TA1501-1820 021001 nanoscience & nanotechnology Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials chemistry Optoelectronics Quantum efficiency 0210 nano-technology Luminescence business Phosphorescence lcsh:Optics. Light Light-emitting diode |
| Zdroj: | Light: Science & Applications, Vol 8, Iss 1, Pp 1-9 (2019) Light, Science & Applications |
| ISSN: | 2047-7538 |
| DOI: | 10.1038/s41377-019-0126-1 |
| Popis: | Phosphor-converted white-light-emitting diodes (pc-WLED) have been extensively employed as solid-state lighting sources, which have a very important role in people’s daily lives. However, due to the scarcity of the red component, it is difficult to realize warm white light efficiently. Hence, red-emitting phosphors are urgently required for improving the illumination quality. In this work, we develop a novel orangish-red La4GeO8:Bi3+ phosphor, the emission peak of which is located at 600 nm under near-ultraviolet (n-UV) light excitation. The full width at half maximum (fwhm) is 103 nm, the internal quantum efficiency (IQE) exceeds 88%, and the external quantum efficiency (EQE) is 69%. According to Rietveld refinement analysis and density functional theory (DFT) calculations, Bi3+ ions randomly occupy all La sites in orthorhombic La4GeO8. Importantly, the oxygen-vacancy-induced electronic localization around the Bi3+ ions is the main reason for the highly efficient orangish-red luminescence. These results provide a new perspective and insight from the local electron structure for designing inorganic phosphor materials that realize the unique luminescence performance of Bi3+ ions. LEDs: Painting the town red Phosphorescent substances that give white-light-emitting diodes a more natural reddish hue can be made by tuning the electron structure of their activator ions. Jun Lin of China’s Changchun Institute of Applied Chemistry, Chinese Academy of Sciences and colleagues combined germanium, lanthanum and bismuth oxides to manufacture a reddish phosphorescent substance that, when added to blue and green phosphors on an LED chip, produced more natural-looking light compared to conventional phosphor-converted white LEDs. LEDs are constantly being improved as an energy-efficient light source, but the colour of the light they emit can be unnaturally white or blue. Fabricating high quality red-emitting phosphors to change this has been a challenge. The researchers developed a substance with a unique reddish photoluminescence caused by electrons localizing around bismuth ions. Their approach offers a new perspective for exploring luminescence in inorganic materials. |
| Databáze: | OpenAIRE |
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