Effect of silica coating on luminescence and temperature sensing properties of Nd3+ doped nanoparticles

Structural and luminescence properties of uncovered YVO4:Nd3+ and core-shell YVO4:Nd3+@SiO2 nanoparticles synthesized via modified Pechini technique were studied. Effect of silica shell thickness on steady state and kinetics luminescence parameters was investigated. Synthesized nanoparticles were used as non-contact optical thermometers operating in the second biological window upon heating-free 808 nm light by monitoring fluorescence intensity ratio between Nd3+ emission bands as a temperature-dependent parameter. Benefits of silica coating on the temperature sensing properties were clearly demonstrated. The best thermal sensitivity was found to be 0.40% K−1 at 299 K, the minimum temperature uncertainty was less than 0.5 K, which is enough for accurate temperature evaluation in the real systems.