Constructing Dual-Emitting via Energy Transfer in Sr₂ScO₃F:Mn⁴⁺,Nd³⁺ Phosphors For High-Performance Temperature Sensing

The development of high-sensitivity thermometers has become increasingly important in recent years as the demand for noncontact optical temperature measurement has grown. Herein, we report a series of Sr₂ScO₃F:Mn⁴⁺,Nd³⁺ (SSOF:Mn⁴⁺,Nd³⁺) phosphors synthesized by the traditional high-temperature solid-state method for high-performance temperature sensing. Sr₂ScO₃F possesses a [ScO6F] octahedron and [SrO9F] tridecahedron, doped Mn⁴⁺ ions occupy the octahedral sites and emit deep red light at 650-750 nm, and doped Nd³⁺ ions occupy the tridecahedral sites and emit near-infrared light. Due to the energy transfer from the Mn⁴⁺ to Nd³⁺ ions, the SSOF:Mn⁴⁺,Nd³⁺ phosphor exhibits intense dual-center emissions. On the basis of the different thermal quenching behaviors of the Mn⁴⁺ and Nd³⁺ ions, high-sensitivity ratiometric thermometers can be achieved using fluorescence intensity ratio technology, and the high relative sensitivity (<i>S</i>_r) and absolute sensitivity (<i>S</i>_a) reached 3.40% K^-1 (at 343 K) and 0.2580 K^-1 (at 483 K), respectively. Our work not only studies the photoluminescence characteristics of SSOF:Mn⁴⁺,Nd³⁺ phosphors but also points out that SSOF:Mn⁴⁺,Nd³⁺ phosphors have important potential applications in optical temperature measurement.