Enhanced luminescent intensity and the thermometric properties of Ag and Pd-decorated YVO4: Bi3+ nanophosphors

In this study, we report on the synthesis and comprehensive characterization of Y 0.99 VO 4 :0.01Bi 3+ nanophosphors decorated with different concentrations of Ag and Pd nanoparticles. X-ray diffraction analysis confirmed that all the samples crystallized in the pure tetragonal YVO 4 phase. Field emission scanning electron microscopy images revealed monodispersed spherical particles with uniform size distribution. Photoluminescent excitation spectra exhibited a broad band with a maximum of 306 nm, while the emission spectra displayed a broad yellow band at 567 nm. Notably, the effects of noble metal decorations were observed, with both 1 mol% Ag/Y 0.99 VO 4 :0.01Bi 3+ and 0.5 mol% Pd/Y 0.99 VO 4 :0.01Bi 3+ samples demonstrating luminescent intensities approximately two-fold and three-fold higher than the undecorated Y 0.99 VO 4 :0.01Bi 3+ , respectively. The Pd-decorated sample exhibited a maximum relative sensitivity of 2.0 % °C −1 at 149 °C, while the Ag-decorated sample showed a sensitivity of 1.75 % °C −1 at 92 °C and 1.23 % °C −1 at room temperature (∼27 °C). These findings underscore the potential of metal-decorated Y 0.99 VO 4 :0.01Bi 3+ nanophosphors for imaging applications.