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As a kind of non-contact temperature detecting technique, optical thermal probes are noninvasive, response quickly and exhibit high spatial resolution. In recent time, optical thermometry strategy based on metal to metal intervalence charge transfer (IVCT) provided a distinct route in this field.Herein, a series of Pr3+ doped titanate and niobate phosphors were fabricated by solid-state reaction and sol-gel method. It is found that the blue emission (3P0→3H4) and red emission (1D2→3H4) of Pr3+ have different temperature response. The fluorescence intensity ratio of red to blue emission exhibits high temperature sensitivity in a certain temperature range. Besides, this two emission peaks are well separated, providing a good signal discriminability for temperature detection. Significantly, the location of IVCT state related to host has great influence on the non-radiative relaxation processes of electrons populated on 3P0 level and 1D2 level. Based on this strategy, the maximum absolute and relative sensitivity reaches as high as 0.40 K-1 and 1.96% K-1 respectively in certain host. These results indicate that the temperature-dependent FIR basing on the interaction between 4f energy levels of Pr3+ and IVCT can be used as a promising thermometric strategy to achieve high temperature sensing performance.