Temperature sensing based on the cooperation of Eu3+ and Nd3+ in Y2O3 nanoparticles

The improvement of temperature sensing performance for optical thermometers based on thermally coupled energy levels of a certain rare earth ion is constrained by the intrinsic operating principle. Here, a novel strategy has been presented for further improving the sensitivity by employing the cooperation of Eu3+ and Nd3+ in Y2O3 nanoparticles. Drastic temperature dependence of the fluorescence intensity ratio between Eu3+ and Nd3+ is achieved in the range from 300 to 510 K. It is demonstrated that such dependence is attributed to the nephelauxetic effect of Eu3+ and each thermally coupled property of Eu3+ and Nd3+ as well as the energy transfer process from Eu3+ to Nd3+. We conclude that such strategy and the investigated nanoparticles have great potential for optical thermometry with high sensing performance.