Photoluminescence properties of Sr 2 MgSi 2 O 7:Pb 2+and tunable emission from UVB to UVC based on ion substitution

Ultraviolet light is a necessary light source for humans. As typical ultraviolet emission materials, Pb2+ doped phosphors have been widely investigated. Here, we report a Pb2+ activated silicate material. Under the excitation of 258 nm ultraviolet light, Sr2MgSi2O7:Pb2+ can emit broadband ultraviolet light with a peak at 333 nm. The luminescence intensity can be adjusted by changing the Pb2+ doping concentration, and the experiments show that the optimum concentration is 0.02. The critical distance for the corresponding concentration quenching was calculated to be 19.92 Å. By gradually decreasing the Sr/Ba ratio, the luminescence wavelength is gradually shifted from 333 to 383 nm due to the increase of Pb2+-O2−covalency. The continuous replacement of Sr by Ba atoms does not change the crystal structure, and the emission wavelength adjustable range is 50 nm. Our research adds new members to the Pb2+-activated phosphor family. At the same time, the successful use of atomic substitution method provides a reference for the adjustment of the emission wavelength of Pb2+ doped materials. © 2020 Elsevier B.V.