Photoluminescent properties of nanostructured Y2O3:Eu3+ powders obtained through aerosol synthesis

Aerosol route as a feasible bottom-up chemical approach for up-converting phosphor particles processing

“…4 and Table 2) revealed the crystal cell parameters did not change significantly after dopants incorporation in comparison to the Y 2 O 3 phase (PDF 89-5591, a = 10.6 Å) due to the small differences in their ionic radii (Y 3+ 0.104 Å, Yb 3+ 0.100 Å, Er 3+ 0.103 Å). After incorporation into the Y 2 O 3 matrix, the Yb 3+ and Er 3+ ions could be randomly distributed into the two nonequivalent crystallographic sites: non-centrosymmetric C 2 at the 24d site and centrosymmetric S 6 (C 3i ) at the 8a site [9]. With regards to that the Y 3+ cation site occupancy refinements of both positions were performed, since the preferential occupation might influence on luminescence efficiency.…”

“…Yttrium oxide posses a cubic crystal structure with a space group, S.G. Ia3-(T 7 h ) in which there are two crystallographically different rare-earth sites, C2 (75%) and S6 (25%); by that, a unit cell is composed of four atom positions, three having a point symmetry C2 and one position with a point symmetry S6 [7]. ters in the host matrix and the overall particle structure and morphology control, which altogether signify the importance of innovative and controllable UCP phosphor processing route in the current research efforts [7][8][9]. Moreover, of particular impor-tance is the controlled synthesis of the host lattice having targeting crystal structure which determines the distance between the dop-ant ions, their relative spatial position, their coordination numbers, and the type of anions surrounding the dopant.…”

“…In our previous work, hot wall aerosol route has been recognized as successfull to obtain submicronic Eu 3+ -doped nanocrystalline down-conversion Y 2 O 3 , (Y 1Àx Gd x ) 2 O 3 and Gd 2 O 3 phosphor particles with advanced structural, morphological and luminescent properties [8,9,16]. It has been demonstrated that the key particle formation parameters are the physico-chemical properties of precursor solution, the manner of aerosol generation and the process parameters like temperature, residence time, and atmosphere determining the mechanisms of aerosol formation, solute precipitation, nucleation, growth and primary nanoparticles aggregation into a spherical assemblage [7].…”

TEM–STEM study of europium doped gadolinium oxide nanoparticles synthesized by spray pyrolysis

“…Gadolinium or Yttrium doped with Europium oxides are important due to their luminescent properties [15,16]. Higher luminescence efficiency and long-term stability of this material are mostly associated with investigating optimum doping concentration, nanostructuring and obtaining overall morphology control.…”

“…All observed transitions are due to the Eu 3+ in C2 and S6 crystallographic sites. In Y 2 O 3 :Eu, the lifetime measurements revealed the quenching effect with the rise of dopant concentration and its more consistent distribution into host lattice due to the thermal treatment [16]. However, there are currently a number of doubts concerning the specific morphological characteristics (roughness, porosity) that affect the quality of the luminescent response.…”