Dual-emissive Eu3+, Tb3+ co-doped Gd2(MoO4)3 phosphor for optical thermometry application

Ratiometric fluorescent sensing materials based on dual-emissive luminescent centers have been widely researched due to their highly stable self-calibrating monitoring performance. In this work, Eu3+, Tb3+ co-doped gadolinium molybdate [Gd2(MoO4)3] phosphors were successfully prepared through a facile precipitation and a following heat treatment process. Dual-emissive Gd2(MoO4)3: Eu3+, Tb3+ phosphor showed characteristic emission peaks at 592, 617, and 703 nm corresponding to the transitions of 5D0–7F1, 5D0–7F2 and 5D0–7F4 for Eu3+ ions, and the other emissions at 488 and 543 nm were ascribed to 5D4–7F6 and 5D4–7F5 transitions for Tb3+, respectively. The temperature sensitivities of Gd2(MoO4)3: Eu3+, Tb3+ based on a multimode fluorescence intensity ratio (FIR) technique were investigated for monitoring temperature changes in the range of 80–450 K. The maximum relative sensitivities of the four modes of FIR (ITb3+/IEu3+) techniques were successfully achieved with range of 0.37–0.50% K−1. The results also demonstrated the high reversibility of Gd2(MoO4)3: Eu3+, Tb3+ phosphor used as a self-calibrating thermometer for thermal-sensing application.