Synthesis and optical temperature sensing performance of NaLa(MoO4)2: Tb3+, Eu3+ phosphors

NaLa(MoO4)(2): Tb3+, Eu3+ phosphors were prepared via the hydrothermal method using sodium citrate as chelating agent, and different morphologies of the samples were obtained through the change of the Na(3)Cit molar ratio to rare earth ions. The NaLa(MoO4)(2): Tb3+, Eu3+ phosphors' structure, morphology, and temperature sensing performance were investigated using XRD (X-ray diffraction) and FE-SEM (Field Emission Scanning Electron Microscope) as well as temperature-dependent emission spectra. The XRD demonstrated that all the materials are body-centered tetragonal phase. The FE-SEM results show that a dosage of sodium citrate could control the NaLa(MoO4)(2): Tb3+, Eu3+ phosphors' morphology. On the basis of the temperature-dependent emission spectra, the FIR (Fluorescence Intensity Ratio) of Eu3+ and Tb3+ in all the samples changed with the temperature and could represent the temperature. Furthermore, the phosphors' sensitivity increased with the value of Cit(3-)/Re3+. Simultaneously, observed from the CIE (Commission International del'Eclairage) chromaticity coordinates, the range of the samples' luminescence color variation expanded with the Cit(3-)/Re3+ increases.