Color modulation and temperature sensing investigation of Gd2O3: 1 mol% Er3+, 1 mol% Yb3+ phosphors under different excitation condition

Abstract

Recently, modulating emission color and increasing temperature sensing sensitivity of rare earth doped materials are imperative because of their applications in colorful display, multiplexed labeling and temperature sensing. In this work, the emission color, radiated from Gd2O3: 1 mol% Er3+/1 mol% Yb3+ phosphors, is modulated through co-excitation condition, which is attributed to the additional co-excited up-conversion processes. The validity of co-excited up-conversion processes are demonstrated via the multi-photon up-conversion processes. More importantly, the temperature-dependent green emissions from Gd2O3: 1 mol%Er3+/1 mol%Yb3+ phosphors under different excitation condition are investigated. The fluorescence intensity ratio (FIR) of 522 and 562 nm (R522/562) exhibits relatively high sensing sensitivities among that of R522/538, R522/553, R522/562 due to the big energy gap. The maximal sensing sensibility (4.1 %K−1) is obtained as the sample is co-excited under 980 and 1550 nm lasers, which is 37% improvement over single 980 nm laser excitation (3.0 %K−1). The results confirm that the co-excited method is promising to serve as an alternative approach for tuning the emission color and enhancing the temperature sensing sensibility of up-conversion materials.