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Abstract: Single-phase broad-band red-emitting Ca3Si2O7:Eu2+ 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 H3BO3 as a flux. The phosphors produced have an intense broad red emission band, with a peak at 603nm, a full width at half maximum of 110nm, and color coordinates of (0.550, 0.438). Concentration quenching occurred at 0.01mol Eu2+. The discussion of the results shows that Eu2+ ions should be accommodated at the Ca-sites of the lattice, dipole–dipole interactions should predominantly govern the energy transfer mechanism among them, and the critical distance between them is ∼31Å. [Copyright &y& Elsevier]

A series of Ce3+ and Eu2+ co-doped SrSi2O2N2 phosphors, whose features qualify them for consideration in white-light UV or blue light-emitting diodes (LEDs), was synthesized via a high temperature solid-state reaction under a reductive atmosphere. The dependence of luminescence properties of the produced powders on the Concentration of an activator (Eu2+) and a coactivator (Ce3+) was investigated. The experimentally recorded luminescence spectra and the calculations of the efficiency of energy transfer from Ce3+ to Eu2+ and the critical distance between Ce3+ and Eu2+ suggest a resonance-type energy-transfer mechanism from Ce3+ to Eu2+ due to dipole-dipole interactions. [ABSTRACT FROM AUTHOR]