A high-sensitivity dual-mode optical thermometry based on one-step synthesis of Mn2+:BaAl12O19–Mn4+:SrAl12O19 solid solution phosphors

Compared with rare earth ions, transition metals have high temperature sensitivity, but the research on thermometry according to only using transition metals were not mentioned in phosphors. In this regard, a series of Mn 2+ :BaAl 12 O 19 –Mn 4+ :SrAl 12 O 19 solid solutions were synthesized by high temperature solid phase method and researched. Although the sample is mixed phase, it can be synthesized in one step to avoid the defects in mixed phase preparation. The co-doping of Mn 2+ /Mn 4+ is achieved by the self-reducing ability of BaAl 12 O 19. It provides the possibility of thermometry doped Mn 2+ /Mn 4+ based on the fluorescence intensity ratio. This material has excellent optical temperature sensing properties from 293 K to 406 K with good recyclability. Therefore, it is suitable for thermometry based on fluorescence intensity ratio with high maximum absolute (0.11 K −1 at 406 K) and relative sensitivity (4.37% K −1 at 293 K), obviously superior to the previously reported which are rare earth ions doped thermometry materials. Based on fluorescence lifetime of Mn 4+ , the maximum relative sensitivity is 4.48% K −1 at 353 K. The Mn 2+ /Mn 4+ co-doped material is reported for the first time. The Mn 2+ :BaAl 12 O 19 –Mn 4+ :SrAl 12 O 19 solid solutions have broad application prospect in the field of fluorescence thermometry, and the dual-mode thermometry makes it has excellent applicability in all aspects. • The Mn 2+ :BaAl 12 O 19 –Mn 4+ :SrAl 12 O 19 solid solution realizes dual-mode thermometry. • The Mn 2+ :BaAl 12 O 19 –Mn 4+ :SrAl 12 O 19 solid solution has high temperature sensitivity. • The Mn 2+ :BaAl 12 O 19 –Mn 4+ :SrAl 12 O 19 solid solution avoids the defects of TCL. • The Mn 2+: BaAl 12 O 19 –Mn 4+ :SrAl 12 O 19 solid solution can be synthesized in one step.