A novel red-emitting phosphor Mg 2 Y 2 Al 2 Si 2 O 12 :Ce 3+ /Mn 2+ for blue chip-based white LEDs.

Traditional white light-emitting diodes (LEDs) (blue chip + YAG:Ce 3+ yellow phosphor) have the limitation of red deficiency, which limits their application in the illumination field. The single cation/anion substitution or co-doping of activators can increase the red component; however, the large energy loss is attributed to the ultra-long Stokes shift and energy transfer. This work attempts to utilize the short-distance Stokes shift and a small amount of energy transfer to increase the red component in two steps. First, based on a large number of previous research results, the Mg 2 Y 2 Al 2 Si 2 O 12 :Ce 3+ phosphor is selected. Second, additional enhancement of the red component in the emission spectrum was achieved by ion co-doping Mn 2+ into Mg 2 Y 2 Al 2 Si 2 O 12 :Ce 3+ . The emission peaks for samples Mg 2 Y 2 Al 2 Si 2 O 12 :Ce 3+ ,Mn 2+ shift from 600 to 635 nm with increase in the concentration of Mn 2+ , and the emission spectra intensity of Mg 1.97 Y 1.93 Al 2 Si 2 O 12 :0.07 Ce 3+ ,0.03 Mn 2+ anomalously increased by ∼37%, which was attributed to the increase in the distance between Ce 3+ ions because of the doping of Mn 2+ ions, and reduction in the concentration of defects in the crystal, resulting in the energy loss decreases of Ce 3+ . The emission peak of Mg 1.97 Y 1.93 Al 2 Si 2 O 12 :0.07 Ce 3+ ,0.03 Mn 2+ shifts to 618 nm and the quantum efficiency was as high as 83.07%. Furthermore, this sample has high thermal stability and the emission intensity was still 80.14% at 120 °C. As such, it has great potential in the application of white LEDs.