Structural and optical characterizations of Ce3+ -doped YSO phosphors via the addition of TEOS.

ABSTRACT

In this work, Y2 O3 phosphors were synthesized utilizing facile sol-gel, combustion, and solid-state techniques. The tested synthesis processes provided various particle sizes from nano to submicron. To synthesize YSOCe3+ via a sol-gel method, tetraethylorthosilicate (TEOS) was used as the precursor for SiO2 . Crystal structure, microstructure, and optical behaviour of the synthesized nanostructured phosphors were studied using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared (FT-IR) spectrometry, and photoluminescence (PL) analyses. FT-IR analysis showed that hydrolysis of TEOS gave rise to the generation of Si-O-Si asymmetrical stretching vibrations. Addition of specific amounts of TEOS resulted in the formation of Y2 SiO5 /Y2 Si2 O7 phosphors with different crystal structures. Upon excitation of the phosphors under 354 nm radiation, there were two strong emission peaks at 395.6 and 424.1 nm, attributed respectively to 5d-2 F5/2 and 5d-2 F7/2 electron transitions of Ce3+ . It was concluded that the most intense PL characteristics belonged to the combination of Y4.67 (SiO4 )3 O, Y2 Si2 O7 , and Y2 SiO5 phosphors.