Synthesis of BaSi 2O 2N 2:Ce 3+,Eu 2+ phosphors and determination of their luminescence properties

BaSi2O2N2:Ce3+,Eu2+ phosphors were successfully synthesized via the solid-state reaction method. Their luminescence properties were experimentally investigated and qualify them for further consideration as components in white light-emitting diodes. In particular, BaSi2O2N2:Eu2+ phosphors have an efficient bluish-green emission band that peaks at 490 nm. Ce3+-doped BaSi2O2N2 showed a bright emission band at 390 nm. A red shift tuning capability of emission bands was achieved by increasing the Eu2+ or Ce3+ contents. Measurements of the intensity of emission spectra suggested a concentration quenching effect for both Eu2+ and Ce3+. Analysis of the experimental results suggests that the enhancement of emission intensity in the produced codoped BaSi2O2N2:Ce3+,Eu2+ phosphors is due to resonance-type energy transfer from Ce3+ to Eu2+ ions, which is predominantly governed by dipole-dipole interaction mechanism. The efficiency of energy transfer was calculated and the critical distance of energy transfer between Ce3+ and Eu2+ was determined as similar to 25 A.