Energy transfer between two luminous centers and tunable emission of La7Nb3W4O30:Dy3+, Eu3+
New tunable-color luminescent materials with single pure phase are one of the main research objectives at present. We synthesize La 7 Nb 3 W 4 O 30 :R (LNWO:R) (R Dy 3+ , Eu 3+ , and Dy 3+ /Eu 3+ ) in air. The high temperature solid-state method is used. We study the purity, crystal phase and structure, luminescence properties, and lifetimes of the samples. Excitation spectrum of LNWO:Dy 3+ comes from the O 2− - Dy 3+ charge transfer band (CTB) and the f – f electron transitions of Dy 3+ . LNWO:Dy 3+ can glow yellow light due to the transitions 4 F 9/2 → 6 H 15/2 , 6 H 13/2 , 6 H 11/2 , and 6 H 9/2 of Dy 3+ . LNWO:Eu 3+ has excitation spectrum due to the O 2− - Eu 3+ CTB and the f – f electron transitions of Eu 3+ . LNWO:Eu 3+ emits the red-orange/red light owing to the transitions 5 D 0 → 7 F 1 , 7 F 2 , 7 F 3 , and 7 F 4 of Eu 3+ . The emitting color of LNWO:Dy 3+ , Eu 3+ can be adjusted by changing the excitation wavelength and the content of Dy 3+ and Eu 3+ because of the double effects of energy transfer among Eu 3+ ions and energy of Dy 3+ . The yellow, red-orange, and red emission of LNWO:Dy 3+ , Eu 3+ is found. The lifetime rises with adding doped-ions concentration owing to the increase of non-radiative transitions. The luminous mechanism is analyzed via energy level diagrams. The research results offer a help for the development of new luminescent materials.
危险品化学品经营许可证（带存储）