A single-phase NaCa2Mg2V3O12:Sm3+ phosphor: Synthesis, energy transfer, and luminescence properties

NaCa2Mg2V3O12:Sm3+ phosphors are successfully prepared in air via solid-state reaction method. The crystal structures, concentration-dependent emission spectra, decay curves, and luminescence properties are investigated. The prepared samples have only a single phase (NaCa2Mg2V3O12). The excitation spectrum of host (NaCa2Mg2V3O12) monitored at 510 nm is observed in the region from 210 nm to 400 nm. The host (NaCa2Mg2V3O12) with excitation at 340 nm shows a strong broadband green emission with a maximum at 510 nm in the range of 400-800 nm. The excitation spectrum of NaCa2Mg2V3O12:Sm3+ phosphor monitored at 618 nm is shown in the region from 210 nm to 550 nm, which includes many absorption peaks. NaCa2Mg2V3O12:Sm3+ phosphor with excitation at 340 nm displays the tunable emission color in the region from green to yellow light with changing Sm3+ concentration, however, that with excitation at 406 nm only emits red light. The optimual Sm3+ concentration is about 4 mol% in NaCa2Mg2V3O12:Sm3+ phosphor. The lifetime of NaCa2Mg2V3O12:Sm3+ phosphor decreases from 929.16 mu s to 832.11 mu s with increasing Sm3+ concentration. The luminous mechanism of NaCa2Mg2V3O12:Sm(3+)phosphor is explained by the configurational coordinate diagram of VO(4)(3- )and energy level diagram of Sm3+ ion. The experimental results are beneficial to the research of other Sm3+-doped luminescence materials.