Bifunctional application of LaBWO:Bi,Sm phosphors with strong orange-red emission and sensitive temperature sensing properties.

Through a solid-phase reaction technique, Sm and Bi co-doped LaBWO phosphors with high emission intensity and sensitive temperature sensing properties have been successfully synthesized. Based on XRD Rietveld refinement, the optimized crystal structure was used as the original model to calculate the band structure and partial density of states (PDOS) by density functional theory (DFT) calculations. The luminescence characteristics of Sm and Bi co-doped LaBWO phosphors were measured and analyzed. In addition, the optimal doping concentrations of Sm and Bi were investigated. The luminescence properties of Sm doped phosphors were optimized by introducing Bi ions. Efficient energy transfer from Bi to Sm ions was observed in LaBWO:Sm, Bi phosphors. An optical temperature sensor with high sensitivity was designed based on the different thermal quenching properties of Sm and Bi ions. In the temperature range of 293-498 K, the optimum absolute sensitivity () and maximum relative sensitivity () were 2.88 %K and 1.32 %K, respectively. These results indicated that the prepared LaBWO:Bi, Sm phosphors have wide application prospects as solid state lighting materials and optical temperature sensors.