Synthesis and photoluminescence characterization of Sm3+/Eu3+ single-doped Gd2MgTiO6 phosphor for LEDs

Trivalent rare earth ions samarium and europium ions were doped into the prepared Gd 2 MgTiO 6 host crystal structure by high temperature solid phase method. XRD patterns show that the synthesized materials belong to the monoclinic structure with space group P 21 / n . Using UV-visible spectroscopy, the band gaps can be calculated to be 4.18, 4.15 and 3.84 eV for host, Sm 3+ and Eu 3+ -doped samples, respectively. For Sm-doped sample excited with 407 nm, the PL spectrum shows three prominent peaks at 565 nm, 603 nm and 649 nm, which are attributed to the transitions of 4 G → 5 / 2 6 H 5/2 , 4 G → 5 / 2 6 H 7/2 and 4 G → 5 / 2 6 H 9/2 , respectively. The 591 nm and 615 nm emissions of Eu 3+ doping correspond to the transitions from 5 D 0 to 7 F 1 and 7 F 2 , respectively. The optimal concentrations are 0.03 mol and 0.09 mol for Sm 3+ and Eu 3+ doping, respectively. The prepared samples can be used in the field of LEDs thanks to lower color temperature CCT=1700∼2200 K and higher color purity >97%.