Luminescence of Eu3+in Two Different Sites of Na3GdSi2O7and Gd3+-Eu3+Energy Transfer

Eu3+ doped sodium gadolinium pyrosilicate phosphors Na3Gd1−xEuxSi2O7 were prepared using a high-temperature solid-state reaction technique. Structural refinement of Na3GdSi2O7 reveals that there are two distinct Gd3+ sites in Na3GdSi2O7 host lattice. The spectroscopic properties of Na3Gd1−xEuxSi2O7 in VUV-UV-vis range and fluorescent lifetimes were investigated. The nonradiative energy-transfer rate KGd-Eu and energy-transfer efficiency ηGd-Eu were discussed. The luminous intensity and CIE chromaticity coordinates of Na3Gd1−xEuxSi2O7 under 172 nm excitation were compared with that of commercial red-emitting phosphor (Y, Gd)BO3: Eu3+.