Color tunable upconversion luminescence and optical thermometry properties of mixed Gd2O3:Yb3+/Ho3+/Er3+ nanoparticles prepared via laser ablation in liquid

The mixtures of Gd 2 O 3 :Yb 3+ /Er 3+ and Gd 2 O 3 :Yb 3+ /Ho 3+ nanoparticles were successfully prepared via pulsed laser ablation in liquid followed by solution mixing. Under excitation of 980 nm diode laser, tunable color from green to red emission was achieved. Based on the thermal linked energy levels, the temperature sensitive upconversion emission was observed. The fluorescence intensity ratio ( FIR ) of I 513–530 nm / I 530–580 nm increased as the elevation of temperature. The absolute sensitivity and relative sensitivity were derived from temperature dependent FIR . The results show that the mixture of Gd 2 O 3 :Yb 3+ /Er 3+ and Gd 2 O 3 :Yb 3+ /Ho 3+ nanoparticles are not only potential candidates for multicolor upconversion luminescence but also promising optical materials for non-contact optical thermometry.