Controlled synthesis and the effects of Gd 3+ substitution, calcination, and particle size on photoluminescence of (Y 0.95− x Gd x Tb 0.05 ) 2 O 3 green phosphor spheres
(Controlled synthesis and the effects of Gd3+ substitution, calcination, and particle size on photoluminescence of (Y0.95-xGdxTb0.05)2O3 green phosphor spheres)