Energy transfer,luminescence properties,and thermal stability of color tunable barium pyrophosphate phosphors

A series of barium pyrophosphate Ba2P2O7(BPO)phosphors doped with Ce3+or Tb3+ions is synthesized via a co-precipitation method under reducing atmosphere.The phase structures,photoluminescence(PL)properties,and thermal stabilities of the samples are characterized by using powder x-ray diffraction(PXRD)and PL spectra.The emission colors of samples can be tuned from blue(0.1544,0.0310)to green(0.2302,0.4229)by changing the doping concentrations of Tb3+under ultraviolet excitation.The energy transfer mechanism between Ce3+and Tb3+in the BPO is dipole–dipole interaction with a critical distance of 25.86°A and an energy transfer efficiency of about 85%,which are determined through the PL spectrum and the decay curve.Moreover,the Ce3+/Tb3+co-doped sample has good thermal stability for temperature quenching,and the emission intensity at 423 K is maintained at 95%measured at 298 K.The above results show that the BPO:Ce3+,Tb3+can serve as a promising candidate of green emitting phosphor for solid-state lighting.