A single-phase NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor: Synthesis, energy transfer, and luminescence properties

Abstract

NaCa 2 Mg 2 V 3 O 12 :Sm 3+ 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 (NaCa 2 Mg 2 V 3 O 12 ). The excitation spectrum of host (NaCa 2 Mg 2 V 3 O 12 ) monitored at 510 nm is observed in the region from 210 nm to 400 nm. The host (NaCa 2 Mg 2 V 3 O 12 ) 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 NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor monitored at 618 nm is shown in the region from 210 nm to 550 nm, which includes many absorption peaks. NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor with excitation at 340 nm displays the tunable emission color in the region from green to yellow light with changing Sm 3+ concentration, however, that with excitation at 406 nm only emits red light. The optimual Sm 3+ concentration is about 4 mol% in NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor. The lifetime of NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor decreases from 929.16 μs to 832.11 μs with increasing Sm 3+ concentration. The luminous mechanism of NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor is explained by the configurational coordinate diagram of VO 43− and energy level diagram of Sm 3+ ion. The experimental results are beneficial to the research of other Sm 3+ -doped luminescence materials.