Influence of rare earth doping and calcination temperature on temperature sensitivity of gadolinium molybdate nanoparticle

Abstract

NaGd(MoO4)2: Er3+/Yb3+ up-conversion fluorescence materials was prepared by a sol-gel method. And the effects of activator ion doping concentration, sensitizer ion doping concentration and calcination temperature on the temperature sensitivity of NaGd(MoO4)2: Er3+/Yb3+ materials were studied. The samples were characterized by XRD, SEM and fluorescence spectra. The temperature sensitivity of different powder was calculated by using the temperature measurement formula of fluorescence intensity ratio. At this time, the results show that the temperature sensitivity is the highest when the concentration of Er3+ is 0.5% in the range of 0.3–2.0% and when the concentration of Yb3+ is 28% in the range of 16–32%. Under the condition of 0.5% Er3+/ 28% Yb3+, a higher value of 0.0268 K−1 can be obtained. Then, the change of temperature sensitivity with doping concentration was analyzed based on the theory of energy transition and the analysis of fluorescence lifetime. In addition, with the calcination temperature increasing from 700 ℃ to 1100 ℃, it is found that the fluorescence intensity and temperature sensitivity of the calcination temperature at 800 ℃ are both great. At the same time, the influence of doping concentration of Er3+， doping concentration of Yb3+ and calcination temperature on the sensitivity was compared. It was found that the influence of Er3+ ion doping concentration was more significant. These results indicate that Er3+ and Yb3+ co-doped NaGd(MoO4)2 powder has a great application prospect in temperature sensing.