Enhanced red emission in Sr.sub. phosphor and spectroscopic analysis for display applications

The particles of the solid solution of strontium molybdate and tungstate (SrMo.sub.0.5W.sub.0.5O.sub.4) were doped with Eu.sup.3+ ions at concentrations of 1, 2 and 4 mol% synthesized by the microwave-hydrothermal method (MHM). The structural analyses of the particles were conducted by XRD with Rietveld Refinement and FT-Raman spectroscopy. The crystallization and growth of particles were investigated by FEG-SEM and proposed a mechanism of particle development involving the steps: nucleation and further growth. The SrMo.sub.0.5W.sub.0.5O.sub.4 presented white emission with the chromaticity coordinates: (0.32; 0.40). The Sr.sub.(1-x)Eu.sub.xMo.sub.0.5W.sub.0.5O.sub.4 samples exhibited an increase in luminescence intensity in the red region as the concentration of Eu.sup.3+ increases, a behavior attributed to the .sup.5D.sub.0 [right arrow] .sup.7F.sub.2 transition of Eu.sup.3+ (623 nm). The Sr.sub.(1-x)Eu.sub.xMo.sub.0.5W.sub.0.5O.sub.4 samples showed high color purity ([almost equal to] 97%), as well as the results of the color reproduction index (CRI) reached 80% level. The radiation luminous efficiency (LER) presented by the samples exhibited values of 322 lm.W.sup.-1. According to the quality of the photometric parameters presented, the samples have attributions for application in solid-state lighting devices. Graphical abstract