Luminescence properties of samarium-doped SiO2–Na2SO4 composite

Comprehensive structural and luminescence study of Sm-doped SiO2–Na2SO4 composite materials  have been conducted. The samples were synthesized by melt-mixing mixture of Na2SO4 and SmF3 into the SiO2 matrix at 1050 °C for 30 min. XRD pattern shows that the  addition of 20% Na2SO4:Sm has no effect on the basic crystal structure of the SiO2. Scanning electron micrograph shows  distinct difference in morphological structure between the composite and host SiO2. From photoexcitation (PE) spectra of the as-synthesized composite, the highest excitation efficiency was observed at 402 nm. The photoluminescence (PL) spectra of as-synthesized composite phosphors obtained under 402 nm excitation consist of five narrow emission bands with peaks at 563, 598, 644, 704 and 784 nm, respectively. These are assigned to the G5/24→HJ6 (J=5/2, 7/2, 9/2, 11/2 and 13/2, respectively) transitions within 4f5 electronic configuration of Sm3+. The highest luminescence intensity was observed  from SiO2-10%Na2SO4:Sm.

► Synthesis of Sm-doped SiO2–Na2SO4 composite phosphor for the first time.
► XRD, SEM and photoluminescence (PL) measurements were carried out.
► Sm-doped composite shows better PL efficiency than that of Na2SO4:Sm.
► SiO2–10%Na2SO4:Sm shows the highest PL efficiency.