Synthesis and luminescence properties of a broad-band red phosphor Ca_3Si_2O_7:Eu~2 for warm white light-emitting diodes

摘要

Single-phase broad-band red-emitting Ca_3Si_2O_7:Eu~2 phosphors, with photoluminescence features that qualify them as candidates for white light-emitting diodes applications, were successfully synthesized via a modified solid-state reaction method that employed H_3BO_3 as a flux. The phosphors produced have an intense broad red emission band, with a peak at 603 nm, a full width at half maximum of 110 nm, and color coordinates of (0.550, 0.438). Concentration quenching occurred at 0.01 mol Eu~2. The discussion of the results shows that Eu~2 ions should be accommodated at the Ca-sites of the lattice, dipoledipole interactions should predominantly govern the energy transfer mechanism among them, and the critical distance between them is ~31 ?.