Tunable photoluminescence properties and non-contact thermometry of Bi3+, Sm3+ co-doped YVO4 phosphors

Bi3+, Sm3+ co-doped YVO4 phosphors with fixed Bi3+ concentration and variable Sm3+ concentrations were synthesized by high-temperature solid-state method. X-ray Rietveld refinement was performed to reveal the crystal structure of the obtained samples. The luminescence properties of dopant ions and matrix were analyzed by fluorescence spectroscopy, and the mechanism of concentration quenching phenomenon and energy transfer behavior among the matrix and dopant ions were investigated. Moreover, the dependence of the luminescence properties of Bi3+ and Sm3+ on temperature was also studied. The red shift of the broad excitation band and the variation of the relative luminescence intensity of the dopant ions caused by the temperature were observed. Both of them were conducive to temperature sensing, and high temperature sensitivities were obtained, which confirmed that Bi3+, Sm3+ co-doped YVO4 phosphors may be a good non-contact thermometer. In addition, the light color of the samples changed in a wide range as Sm3+ concentration and temperature rising.