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

Abstract A novel green phosphor, Sr 2 MgB 2 O 6 :Tb 3+ ,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 5 D 4 → 7 F 5 transition. 9 mol.% of Tb 3+ 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 Sr 2 MgB 2 O 6 :0.09Tb 3+ ,0.09Li + phosphor decreased continuously to 72.1% at 300 °C with increasing temperature, and the activation energy of thermal quenching ( E a ) was calculated to be 0.175 eV, moreover, the quantum yield excited by 368 nm was measured as 11.1%. A green emission LED was made by coating Sr 2 MgB 2 O 6 :0.09Tb 3+ ,0.09Li + phosphor on a NUV (365-370 nm) chip. Our results showed that Sr 2 MgB 2 O 6 :Tb 3+ ,Li + is a kind of potential green-emitting phosphor and features good thermal stability.