Synthesis and luminescent properties of Ba_2V_2O_7：Sm^3

Samarium doped pyrovanadate Ba_2V_2O_7：Sm^3＋ phosphors were synthesized by traditional high-temperature solid-state reaction method. The phase and the structure of the samples were characterized by powder X-ray diffraction（XRD）, and the luminescent properties and the energy transfer mechanism of the material were investigated using quantitative photoluminescence（PL） spectroscopy. The excitation spectrum of the sample exhibited a broad ultraviolet（UV） band with maximum at around 341 nm due to V–O charge transfer transition of the host. The emission spectrum displayed a yellow-greenish broadband（peaking at around 498 nm） coming from the host Ba_2V_2O_7 and three narrow peaks（at 561, 599 and 646 nm） attributed to the dopant Sm^3＋ ions. The PL spectra revealed the energy transfer from the host to the Sm^3＋ ions. In addition, the color coordinates and the color temperature of the phosphor Ba_（1.95）V_2O_7：5%Sm^3＋ were（0.314, 0.365） and 6135 K, respectively, under 365 nm excitation, suggesting it to be a candidate of single-phase converting phosphors for white-light-emitting diodes（WLEDs） with near-UV chips.