| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1522843 | Materials Chemistry and Physics | 2013 | 6 Pages |
•Translucent nanoceramics of Cr3+:MgAl2O4 have been fabricated.•Applied pressure strongly affects luminescence spectra of Cr3+:MgAl2O4 ceramics.•Significant changes in excitation spectra with applied pressure were observed.•Increase of the sintering pressure strongly affects the dynamics of the Cr ions.
The effect of the applied sintering pressure on luminescence and excitation spectra of Cr3+ doped MgAl2O4 nanoceramics was investigated. It was found that the intensity of 2E → 4A2 phosphorescence decreased significantly when pumped directly into 4T1 band. The effect was extremely strong for nanoceramics sintered at higher pressures. Moreover, the intensity of 4A2 → 4T1 band in excitation spectra drastically decreased with sintering pressure compared to 4A2 → 4T2 band. This behavior was related to trigonal distortion of Oh symmetry of Cr3+ ion which increases with decreasing the size of nanocrystals resulting in enhancement of the 4T1 → 4T2 nonradiative pathway due to decrease of ΔE (4T1, 4T2) energy gap.
