Optimization of photoluminescence of Y₂O₃:Eu and Gd₂O₃:Eu phosphors synthesized by thermolysis of 2,4-pentanedione complexes

Abstract

Spherical shaped nanoparticles of series Y(2 - x)Eu(x)O(3) (x = 0.06, 0.10, 0.20, and 2) and Gd(2 - x)Eu(x)O(3) (x = 0.06, 0.10) were prepared by thermolysis of 2,4-pentanedione complexes of Y, Gd, and Eu. The bixbyite phase of Gd(2 - x)Eu(x)O(3) samples was formed at 500 degrees C, whereas the thermal decomposition of Y and Eu complexes' mixtures occurred at higher temperatures. Linearity in the concentration dependence on lattice parameter confirmed the formation of solid solutions. The distribution of Eu(3+) in Gd(2 - x)Eu(x)O(3) was changed with thermal annealing: in the as-prepared sample (x = 0.10) the distribution was preferential at C(3i) sites while in the annealed samples, Eu(3+) were distributed at both C(2) and C(3i) sites. Rietveld refinement of site occupancies as well as emission spectra showed a random distribution of cations in Y(2 - x)Eu(x)O(3). The photoluminescence (PL) measurements of the sample showed red emission with the main peak at 614 nm ((5)D(0)-(7)F(2)). The PL intensity increased with increasing concentration of Eu(3+) in both series. Infrared excitation was required to obtain good Raman spectra. The linear dependence of the main Raman peak wavenumber offers a non-destructive method for monitoring the substitution level and its homogeneity at the micron scale.

Raman spectroscopic investigation of lanthana‐doped neodymium‐yttria transparent ceramics

“…[14] The intensity of Raman bands decreases, which means the symmetry of the crystalline structure is lowered, and similar results have also been reported in Eu 3+ -doped Y 2 O 3 [15] and Yb 3+ -doped Y 2 O 3 [16,17] compounds. Compared to the La 2 O 3 -undoped specimen, it is apparent that each band of (Nd 0.01 La x Y 0.99−x ) 2 O 3 (x = 0.05, 0.10) suffers a red shift due to the weak bond strength of La-O and heavy mass of La 3+ ion, as a consequence of which the phonon energy is slightly reduced.…”

Swift heavy ion induced structural and optical properties of Y2O3:Eu3+ nanophosphor

“…C 3i site has centre of inversion symmetry and so only the magnetic dipole transitions are allowed whereas C 2 site does not have inversion symmetry and hence both electric and magnetic dipole transitions are allowed [14]. The calculated values of C 3i /C 2 site occupancies and the positions (x, y, z) of yttrium and oxygen ions in Eu 3+ doped Y 2 O 3 are given in Table 1.…”

Luminescent Properties of SrGeO3:Eu3+Red Emitting Phosphors for Field Emission Displays

“…2a. 20 Fig . 2b shows the emission spectra of Sr 1-x GeO 3 :xEu 3+ (x = 0.01, 0.02, 0.03, 0.04, 0.05) phosphors excited at 393 nm.…”