Sr 8 ZnSc(PO 4 ) 7 :Eu 3+ ,Li + novel red-emitting phosphors: Synthesis and photoluminescence properties

Abstract An effective strategy based on the host composition design has been adopted to obtain novel high luminescent efficiency red phosphor Sr 7.6 Zn 1- x Sc(PO 4 ) 7 :0.04Eu 3+ , x Li + . This research reveals that Li + ions co-doping can offer charge compensation in host Sr 8 ZnSc(PO 4 ) 7 with 5% mol Eu 3+ doped and produce oxygen vacancies as the sensitizer transferring energy to nearby Eu 3+ . Meanwhile, Li + ions can assist raising grain sizes of Sr 7.6 Zn 1- x Sc(PO 4 ) 7 :0.04Eu 3+ , x Li + phosphors by lowering their melting temperature, further improve their luminescence properties. The luminescence intensity of 595 and 618 nm emission bands of the optimal phosphor Sr 7.6 Zn 0.97 Sc(PO 4 ) 7 :0.04Eu 3+ ,0.03Li + achieved 2.932 and 3.316 times increase compared with the sample without Li + ions incorporated, and it presented 1.26 times greater intensity than commercially red phosphor DS-200. Meanwhile, it also presented excellent thermal stability. Thus, the novel phosphors Sr 7.6 Zn 1- x Sc(PO 4 ) 7 :0.04Eu 3+ , x Li + show the potential application value on WLEDs.