Enhanced visible to near infrared downshifting in Ce3+/Yb3+-co-doped yttrium aluminum garnet through Pr3+ doping

Novel YAG:Ce 3+ , Pr 3+ , Yb 3+ phosphors were synthesized using a high temperature solid state reaction method. The XRD patterns revealed that the obtained samples belong to the single phase YAG. The optical spectra demonstrated that Pr 3+ could be a bridge to facilitate the energy transfer from Ce 3+ to Yb 3+ in the YAG host. Blue light excited Ce 3+ and a yellow emission from Ce 3+ together with a near infrared emission of Yb 3+ was obtained. The effect of Pr 3+ doping on the energy transfer efficiency was explored. When the doping concentration of Pr 3+ increased, the yellow emission intensities of Ce 3+ decreased and the near infrared emission intensity of Yb 3+ increased monotonously. Hence, the efficiency of energy transfer from Ce 3+ to Yb 3+ is enhanced by the addition of Pr 3+ , implying that the YAG:Ce 3+ , Pr 3+ , Yb 3+ phosphors are promising downshifting materials and have the potential to be used in Si-based solar cells.