Difference in the luminescence properties of orthorhombic and monoclinic forms of Y{sub 2}GeO{sub 5}:Ln (Ln = Tb{sup 3+} and Dy{sup 3+})
Highlights: • Improved emission colour purity with orthorhombic form of Y{sub 2}GeO{sub 5}. • Non-stationary quenching exists in orthorhombic and monoclinic forms of Y{sub 2}GeO{sub 5}:Tb. • Ion pair formation and cross relaxation quenching operating for Y{sub 2}GeO{sub 5}:Dy samples. - Abstract: The luminescence properties of Tb{sup 3+} and Dy{sup 3+} doped orthorhombic and monoclinic forms of Y{sub 2}GeO{sub 5} are significantly different. Orthorhombic Y{sub 2}GeO{sub 5} doped with Tb{sup 3+} and Dy{sup 3+} ions gives bright green and blue emission upon UV light excitation with CIE coordinates (0.25, 0.46) and (0.25, 0.24), respectively. The monoclinic Y{sub 2}GeO{sub 5} doped with these ions exhibits light green and yellowish white emissions, respectively. This has been attributed to the differences in crystallographic environments around Y{sup 3+} ions in orthorhombic and monoclinic forms of Y{sub 2}GeO{sub 5}. Quantum yield of emission for orthorhombic Y{sub 2}GeO{sub 5}:Tb (∼29%) is significantly higher than that of the monoclinic Y{sub 2}GeO{sub 5}:Tb (∼14%). Lifetime values corresponding to {sup 4}F{sub 9/2} level of Dy{sup 3+} ions in both monoclinic and orthorhombic forms of Y{sub 2}GeO{sub 5} follow an opposite trend with respect to {sup 5}D{sub 4} level of Tb{sup 3+} ions. This is attributed to difference in the concentration quenching mechanism operating for Tb{sup 3+} and Dy{sup 3+} ions.
- OSTI ID:
- 22475729
- Journal Information:
- Materials Research Bulletin, Journal Name: Materials Research Bulletin Vol. 64; ISSN MRBUAC; ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
Similar Records
Synthesis and luminescent properties of Tb{sup 3+}-activated yttrium indium germanate phosphor
A novel green emitting phosphor Ca{sub 2}GeO{sub 4}:Tb{sup 3+}
Related Subjects
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COLOR
CONCENTRATION RATIO
CRYSTALLOGRAPHY
DOPED MATERIALS
DYSPROSIUM ADDITIONS
EXCITATION
GERMANATES
IMPURITIES
ION PAIRS
LUMINESCENCE
MONOCLINIC LATTICES
ORTHORHOMBIC LATTICES
RELAXATION
SYNTHESIS
TERBIUM ADDITIONS
ULTRAVIOLET RADIATION
VISIBLE RADIATION
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS