Densification and Photoluminescence Improvement of Y[sub 2]O[sub 3] Phosphor Particles Prepared by Spray Pyrolysis

Synthesis and characterization of manganese-doped zinc orthosilicate phosphor powders

“…Presumably, prolongation of heating reduced the porosity and, therefore, the scattering of UV light, enhancing the emission efficiency of powders. Similar results have also been observed from europium-doped phosphor particles that are prepared by spray pyrolysis [23]; the densification of porous Y 2 O 3 :Eu particles greatly improves luminescence intensity. Restated, luminescence intensity due to the d-d transition of Mn 2+ in Zn 2 SiO 4 nanoparticles herein depends not only on the dopant content and improved crystallinity, but also on the texture of the powder.…”

Facile and Controllable Synthesis of Monodisperse CaF2 and CaF2:Ce3+/Tb3+ Hollow Spheres as Efficient Luminescent Materials and Smart Drug Carriers

“…The reason might be that IBU molecules can be adsorbed onto the surface of mesoporous CaF 2 :Ce 3 + /Tb 3 + hollow spheres, and the organic groups in IBU with high vibrational frequencies from 1000 to 3500 cm À1 will strongly quench the emission of Tb 3 + in IBU-CaF 2 :Ce 3 + /Tb 3 + . [53] The quenching effect would disappear and the PL intensity be almost restored when the release of IBU from CaF 2 :Ce 3 + /Tb 3 + sample is complete, as shown in Figure 12 B. This characteristic may have potential as a probe for monitoring or tracking the drug release process, that is, the CaF 2 :Ce 3 + /Tb 3 + hollow spheres can be potentially used as a smart drug carrier.…”

“…[52] Furthermore, the enlargement of the crystallite size means a major decrease in bulk defects, which is also very beneficial for the luminescence efficiency of phosphor particles. [53] Accordingly, the PL quantum efficiency of the CaF 2 hollow spheres increases with increasing particle size (65 % for 300 nm, 70 % for 480 nm, 72 % to 750 nm, and 77 % for 930 nm), as shown in Figure 10 b. In addition, the PL quantum efficiencies of the as-prepared CaF 2 :Ce 3 + /Tb 3 + samples can almost reach or even exceed that of commercial Ce 3 + /Tb 3 + -doped aluminate phosphor (star in Figure 10) under the same excitation conditions (l ex = 306 nm).…”

Tm3+‐Doped Y2O3 Nanocrystals: Rapid Hydrothermal Synthesis and Luminescence

“…[5][6][7][8][9] Recently our group has reported on the morphologycontrolled synthesis of europium-activated Y 2 O 3 nanoparticles under supercritical conditions. [10] Over the last decade, many methods for the synthesis of rare earth oxide doped Y 2 O 3 phosphors have been reported, including solution combustion method, [11] sol-gel method, [12] spray pyrolysis method, [13] hydrothermal synthesis [14] precipitation [15][16][17][18][19][20] [15] and solvothermal refluxing method. [16,17] Among the many different methods listed above, hydrothermal synthesis meets the increasing demand for the direct preparation of crystalline ceramic powders and offers a low temperature alternative to conventional powder synthesis technique in the production of anhydrous oxide powders.…”