| Autor: |
den Engelsen, D, Fern, GR, Ireland, TG, Harris, PG, Hobson, PR, Lipman, A, Dhillon, R, Marsh, PJ, Silver, J |
| Jazyk: |
angličtina |
| Rok vydání: |
2016 |
| Předmět: |
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| Popis: |
Copyright © The Author(s) 2016. Herein we describe the investigation of transmission electron microscopeof non-doped Y2O3 and Y2O3 doped with Eu3+ in a transmission electron microscope (TEM) equipped with a spectrometer to detect cathodoluminescence from individual particles. Each submicron particle was made up of nanometre sized crystals. We found that these crystals showed a broad emission band at 353 nm upon bombardment with 200 keV or 80 keV electrons. Upon increasing the Eu3+ concentration from 0 to 2 mol% this UV/blue emission was gradually quenched: at Eu3+ concentrations >2 mol% no UV/blue emission was detected, only the well-known cathodoluminescence (CL) spectrum of Y2O3:Eu3+ could be recorded. This UV/blue emission has been attributed to the intrinsic luminescence of Y2O3 caused by self-trapped excitons. We found that the UV/blue luminescence was strongly temperature dependent and that the trap depth of the self-trapped excitons was 0.14 eV. The ratios of the spectral radiances of 5D1 → 7FJ and 5D0 → 7FJ (J = 0, 1...6) Eu3+ transitions in the CL-TEM spectra of Y2O3:Eu3+ at low Eu3+ concentrations was about a factor of 10 larger than those recorded at 15 keV. This phenomenon has been explained by absorption of the intrinsic luminescence of Y2O3 by Eu3+. The EPSRC and the Technology Strategy Board (TSB) funded the PURPOSE (TP11/MFE/6/I/AA129F; EPSRC TS/G000271/1), CONVERTED (JeS no. TS/1003053/1) and PRISM (EP/N508974/1) programs. The TSB for funding the CONVERT program. We are grateful to the EPSRC and the Technology Strategy Board (TSB) for funding the PURPOSE (TP11/MFE/6/I/AA129F; EPSRC TS/G000271/1), CONVERTED (JeS no. TS/1003053/1) and PRISM (EP/N508974/1) programs. We are also grateful to the TSB for funding the CONVERT program. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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