Controlling optical temperature detection of Ca3Al2O6: Yb3+,Er3+ phosphors through doping

This work introduces a method to effectively improve optical temperature detection of novel Ca3Al2O6:Yb3+,Er3+ through co-doping with Ba2+, Mg2+, Y3+, La3+ and Lu3+ as well as the control of excitation power. The fluorescence intensity ratio of the green emissions at 526 nm and 551 nm in Ca3Al2O6:Yb3+-Er3+ was studied as a function of temperature in the temperature range from 298 K to 573 K. By analyzing the temperature dependent upconversion spectra, total emission intensity, ratios of fluorescence intensity, and sensitivity, the effect of doping ions on the optical temperature detection of Ca3Al2O6:Yb3+, Er3+ is studied. The relative and absolute temperature sensitivity of Ca3Al2O6:Yb3+,Er3+ can be effectively enhanced by co-doping with Ba2+, Mg2+, Y3+, La3+, and Lu3+ ions and controlling excitation powers. The temperature sensitivity of Ca3Al2O6:6%Yb3+, 0.6%Er3+, 1.2%Mg2+ can reach a maximum relative sensitivity of 0.0078 K−1 at 145 K, which is higher than the values in some reported works.