Luminescence properties of Sr2MgB2O6:Tb3+,Li+ green-emitting phosphor

A novel green phosphor, Sr2MgB2O6:Tb3+,Li+ for white light-emitting diodes was prepared by solid-state reactions, and its structure and luminescence properties were investigated. The excitation and emission spectra indicated that this as-prepared phosphor could be effectively excited by ultraviolet 368 nm, and exhibited bright green emission centered at 545 nm corresponding to the D-5(4) -> F-7(5) transition. 9 mol.% of Tb3+ was shown to be optimal. Good green emissions with the CIE chromaticity coordinates (0.262, 0.583) could be achieved. Furthermore, the integrated emission intensity of Sr2MgB2O6:0.09Tb(3+),0.09Li(+) phosphor decreased continuously to 72.1% at 300 degrees C with increasing temperature, and the activation energy of thermal quenching (Ea) was calculated to be 0.175 eV, moreover, the quantum yield excited by 368 run was measured as 11.1%. A green emission LED was made by coating Sr2MgB2O6:0.09Tb(3+),0.09Li(+) phosphor on a NUV (365-370 nm) chip. Our results showed that Sr2MgB2O6:Tb3+,Li+ is a kind of potential green-emitting phosphor and features good thermal stability.