Lasing in spherically shaped Y2O3-ZnO nanocomposites

Specific features of the structure of ZnO nanocrystals grown in pores of Y2O3 spherical matrices

“…As a result, an alternative approach to ZnO formation was proposed in [16,17]: nanocrystals are grown in mesopores of monosize nano-and submicron Y 2 O 3 spheres [18][19][20][21][22] with the formation of Y 2 O 3 matrixZnO filler nanocomposites. The zinc oxide nanophase formation in a pore facilitates the slow removal of gaseous products of the zinc nitrate thermolysis reaction (O 2 and NO 2 ); thus, the conditions for retaining oxygen during the ZnO formation are formed.…”

Size-dependent luminescence of spherical Y2O3:Er nanoparticles

“…There are reports on the use of such powders as luminous coat ings of luminescent lamps, scintillators, and tempera ture sensors. The synthesis process in question allows one to obtain nanometer sized, regularly shaped spherical particles having a size distribution less than 15% [2,3]. When the sphere diameter is on the order of the emission wavelength of a phosphor, its lumines cence characteristics are highly dependent not only on the composition of the material but also on its geomet ric shape.…”

“…As a result, the spontaneous luminescence of a rare earth related emission center may be either amplified or weakened, and the luminescence lifetime may vary [2]. Acting as optical resonators, spherical particles enable low threshold lasing, which allows one to produce high brightness phosphors based on yttria nanospheres [3].…”

“…EXPERIMENTAL Nanocrystalline Y 2 O 3 :Er spheres were prepared through homogeneous precipitation with urea (extra pure grade (NH 2 ) 2 CO), followed by low temperature thermolysis (t = 600-800°С) of the resultant amor phous material [5]. As starting chemicals, we used yttrium oxide (Y 2 O 3 , 99.999%) and erbium oxide (Er 2 O 3 , 99.999%), which were dissolved in nitric acid of appropriate concentration to give Y(NO 3 ) 3 and Er(NO 3 ) 3 solutions. To obtain spheres, the Y(NО 3 ) 3 and Er(NО 3 ) 3 solutions were added dropwise to an aqueous urea ((NH 2 ) 2 CO) solution.…”

“…As starting chemicals, we used yttrium oxide (Y 2 O 3 , 99.999%) and erbium oxide (Er 2 O 3 , 99.999%), which were dissolved in nitric acid of appropriate concentration to give Y(NO 3 ) 3 and Er(NO 3 ) 3 solutions. To obtain spheres, the Y(NО 3 ) 3 and Er(NО 3 ) 3 solutions were added dropwise to an aqueous urea ((NH 2 ) 2 CO) solution. The mixture was then heated with constant stirring to t = 90°C over a period of 2 h. The sphere diameter was controlled by varying the Y(NO 3 ) 3 /(NH 2 ) 2 CO molar ratio.…”