Synthesis and Luminescence Characterization of Novel Red-Emitting Phosphors Based on Eu-Activated KSr(MoO) Molybdates for w-LEDs.

In this work, trivalent europium (Eu) ion activated KSr(MoO) red phosphors have been synthesized through high-temperature solid-state reaction method at 750 ℃. Detailed analysis was conducted on the phase purity, morphology, and luminescence properties of the synthesized phosphors. X-ray diffraction (XRD) confirmed the successful formation of KSr(MoO):Eu phosphors with pure phase with space group С. The photoluminescence (PL) spectroscopy was used to record the excitation and emission spectrum of Eu activated KSr(MoO) phosphor. Under the excitation of 280 nm, the resultant samples exhibited the characteristic emissions of Eu ions corresponding to the D→F transitions. The optimal doping concentration of Eu ions was determined to be 35 mol%. Concentration quenching mechanism was identified as the interaction of near-neighbor ions. The chromaticity coordinates of KSr(MoO):35 mol%Eu were (0.659, 0.340) with a corresponding high color purity of 99.8%. The prepared KSr(MoO):35 mol%Eu phosphor had good thermal stability with temperature quenching temperature (T > 420 K) and high activation energy (E = 0.267 eV). The exhaustive findings from this study form the basis for advocating the application of these phosphors in light-emitting devices.