[Ru(dipy)3]2+@SiO2 Nanophosphor as Temperature Sensor: Photobleaching Cheating

Abstract

We used a 55 nm [Ru(dipy)₃]²⁺@SiO₂ nanophosphore as a temperature sensor under photobleaching conditions. We have calibrated these nanoparticles for temperature measurements using/analyzing both luminescence intensity and decay time change. We show that an exposure to a 405 nm semiconductor laser with a power flux density of 2 kW/cm² leads to a two-fold decrease in luminescence intensity over time. At the same time (4 h), the characteristic decay time of the luminescence decreases by approximately half. We demonstrate that a ratiometric method is more reliable for temperature measurements in the range from 300 to 350 K. This method takes approximately half the time required to measure the kinetics of luminescence decay.