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 YSO:Ce3+ 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 354nm radiation, there were two strong emission peaks at 395.6 and 424.1nm, 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.