Structure and Photoluminescence Properties of Sm3+ Ion-Doped YInGe2O7 Phosphor

A new phosphor, Sm3+ ion-doped YInGe₂O₇, was synthesized using a planetary ball mill solid state reaction. The XRD patterns show that all of the peaks can be attributed to the monoclinic YInGe₂O7 crystal structure when the Sm3+ ion concentration is increased up to 20 mol %. Under an excitation wavelength of 404 nm, the Sm3+ intra-4f transition appears in the emission spectrum including two stronger emission peaks located at 560-570 nm and 598 nm correspond to the 4G5/2 → ⁶H5/2 and ⁴G5/2 → ⁶H7/2 transitions, respectively, and another weak emission peak located at 645 nm is due to the ⁴G5/2 → ⁶H9/2 transition. The decay time decreases from 4.5 to 0.8 ms as Sm3+ ion concentrations increase from 1 to 20 mol %, and the decay mechanism of the ⁴G5/2 → ⁶H7/2 transition is a single decay component between Sm3+ ions only. The concentration quenching effect occurs when the Sm3+ ion concentration is higher than 3 mol %. The CIE color coordinate of Y0.97Sm0.03InGe₂O₇ phosphor is at x = 0.457 and y = 0.407, which is located in the orange-yellow light region.