Probing the site occupancy of dopants in deep red-NIR emitting LiAl5O8: Eu3+, Cr3+ and Fe3+ nano phosphors using photoluminescence and X-ray absorption spectroscopy
| Autor: | Sitakanta Panda, P. Vinodkumar, B.S. Panigrahi, Madhusmita Sahoo, U. Madhusoodanan |
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| Rok vydání: | 2021 |
| Předmět: |
X-ray absorption spectroscopy
Photoluminescence Materials science Absorption spectroscopy Dopant Scanning electron microscope Mechanical Engineering Doping Metals and Alloys Analytical chemistry Phosphor 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Mechanics of Materials Materials Chemistry Emission spectrum 0210 nano-technology |
| Zdroj: | Journal of Alloys and Compounds. 857:157615 |
| ISSN: | 0925-8388 |
| DOI: | 10.1016/j.jallcom.2020.157615 |
| Popis: | Eu3+, Cr3+ and Fe3+ doped LiAl5O8 nano phosphors were synthesized through the solution combustion synthesis route in a single step. The powder XRD patterns of the as-prepared samples indicated a single phase and highly crystalline inverse spinel system. Scanning electron microscopy (SEM) image showed a highly compacted morphology of nanoparticles with an average particle size of 60 nm. Optimization of dopant concentration enhanced the photoluminescence (PL) from Eu3+, Cr3+ and Fe3+ with 100% color purity suggesting them as potential deep red-NIR emitting phosphors. Time-resolved emission spectroscopy (TRES) studies indicated the presence of Fe3+ at more than once site. The local coordination geometries of Eu3+ and Fe3+ were investigated using X-ray absorption spectroscopy (XAS) for the first time. The XAS studies confirmed the occupancy of Fe3+ at Al3+-octahedral (Oh), Al3+-tetrahedral (Td) and Li+-Oh sites, and Eu3+ at distorted Li+-Oh site only, corroborating the cause of the unusually broad and deep red-NIR emission of Fe3+ and the deep red emission of Eu3+. |
| Databáze: | OpenAIRE |
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