Luminescent properties of UV excitable blue emitting phosphors MSr4(BO3)3:Ce3+ (M = Li and Na)

A series of Ce3+ doped novel borate phosphors MSr4(BO3)3 (M = Li or Na) were successfully synthesized by traditional solid-state reaction. The crystal structures and the phase purities of samples were characterized by powder X-ray diffraction. The optimal concentrations of dopant Ce3+ ions in compound MSr4(BO3)3 (M = Li or Na) were determined through the measurements of photoluminescence spectra of phosphors. Ce3+ doped phosphors MSr4(BO3)3 (M = Li or Na) show strong broad band absorption in UV spectral region and bright blue emission under the excitation of 345 nm light. In addition, the temperature dependences of emission spectra of M1+xSr4−2xCex(BO3)3 (M = Li or Na) phosphors with optimal composition x = 0.05 for Li and x = 0.09 for Na excited under 355 nm pulse laser were also investigated. The experimental results indicate that the M1+xSr4−2xCex(BO3)3 (M = Li or Na) phosphors are promising blue emitting phosphors pumped by UV light.

Research highlights
► Novel blue emitting phosphors borate MSr4(BO3)3 (M = Li or Na) were prepared first.
► Luminescent properties of phosphors borate MSr4(BO3)3 (M = Li or Na) were investigated extensively as candidates of blue emitting phosphor used for UV excited LED.
► The optimal concentrations of dopant Ce3+ ions in compound MSr4(BO3)3 (M = Li or Na) were determined as 0.05 for Li and x = 0.09 for Na excited by UV light respectively.