Luminescence of Sm 3+ Ions Sensitized by a TiO 2 Matrix

Ti 1- x Sm x O 2- x /2 ( x = 0.025, 0.05, and 0.1) solid solutions with the anatase structure were synthesized by the precursor method and characterized by x-ray diffraction and scanning electron microscopy. Titanium glycolate Ti(OCH 2 CH 2 O) 2 in which Ti was partially replaced by Sm was used as the precursor. The Ti 1- x Sm x O 2- x /2 solid solutions exhibited intense reddish-orange luminescence at room temperature upon excitation at 350 nm. The luminescence properties of the compounds were due to f 5 -intraconfigurational transitions of Sm. The highest luminescence intensity was achieved for Ti 1- x Sm x O 2- x /2 with x = 0.05. The chromaticity coordinates and correlated color temperature values were close to those typical of red phosphors.