Hydrothermal Synthesis of SrMoO4:Eu3+, Sm3+ Phosphors and Their Enhanced Luminescent Properties Through Energy Transfer

Eu3+ and Sm3+ co-doped SrMoO4 phosphors have been successfully prepared via a simple surfactant-free hydrothermal method. The as-prepared phosphors present dumbbell-like agglomerates and comprise of many nanoparticles of 150–300 nm in diameter. Eu3+ and Sm3+ co-doped SrMoO4 phosphors display all the characteristic excitations and emissions of Eu3+ and Sm3+. The introduction of Sm3+ can generate a strong excitation line at 403 nm, originating from the 6H5/2 → 4K11/2 transition of Sm3+, which significantly broadened the excitation region for matching the near ultraviolet light emitting diodes (∼400 nm). And Sm3+ ions can transfer the absorbed energy to Eu3+ ions efficiently, so the intensity of the main emission peak at 614 nm due to 5D0 → 7F2 transition of Eu3+ are strengthened by the co-doping of Sm3+. The doping concentration of Eu3+/Sm3+ was optimized. In addition, the possible energy transfer mechanism has been investigated and is discussed in detail.